# \[CRITICAL\] Tycoon Unjoinable “Network Connection Lost” After 15min – Matchmaking Still Sends Players **URL:** \ **Category:** Issues and Bug Reporting\ **Tags:** open, fortnite-creative, unreal-editor-for-fortnite, fortnite\ **Created:** [June 17, 2025, 1:41pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223 "2025-06-17T13:41:42Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 17, 2025, 1:41pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/1 "2025-06-17T13:41:42Z")
### Summary Tycoon Island gets in a bugged state after 15 minutes playtime with 8 clients. If any player leaves, and a new one tries to join, he will never be able to join. The matchmaking keeps pushing players to the island, and each and every one of them will fail to connect. It completely kills any traction for our island so we have delisted it for now. Support would be greatly appreciated. ### Please select what you are reporting on: Creative ### What Type of Bug are you experiencing? Matchmaking ### Steps to Reproduce 1. You need 8 clients to reproduce this issue, with less accounts you need to wait longer before it appears. E.g. with 2 clients it takes around 60 minutes. 2. Join with all 8 clients the island code 9524-0220-6933 on the same region to ensure you enter the same server instance. 3. Wait around 15 minutes 4. Rejoin with any of the accounts It’s best to keep clients connected for first 15 minutes, rejoining is fine to reproduce as often as you want, but the more players are in the game the faster this issue pops up. ### Expected Result You should be able to enter the game. ### Observed Result You receive a title: ‘THERE WAS A PROBLEM’ with subtext: ‘Network Connection Lost’ ### Platform(s) PC/ XBOX Social Network ### Island Code 9524-0220-6933 ### Upload an image ![networkconnectionlost.jpg](https://d3kjluh73b9h9o.cloudfront.net/original/4X/7/5/5/755f1ec0d6128d89f832f9740dadad95cdd7c58b.jpeg) ### Additional Notes We have done extensive testing to replicate the issue for the past few days, and found with the more clients you try, the faster the issue appears. Our next steps will be figuring out what causes this, but if FN could look into this, the problem will be resolved much faster. We don’t have access to extensive logs unfortunately, and have to delete certain devices, and test again, and keep doing this until we found the cause. The biggest problem with this bug is that currently the Matchmaking engine see’s free space in this server instance, and as result sends EVERY player who is in matchmaking to this instance. Each one will fail to connect and we are losing around 99% of the players who are trying to join through public matchmaking. We have worked countless hours developing this Tycoon and it’s our third one, any support would be greatly appreciated. ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 17, 2025, 1:52pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/3 "2025-06-17T13:52:14Z")
If you need clients during reproduction, we’re happy to join on short notice, just let us know. Thanks in advance. ---
**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\ **Post date:** [June 17, 2025, 4:12pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/4 "2025-06-17T16:12:00Z")
hi @thrax207 , In the Uk, 66Mb/s Max BT broadband whilst running the average throughput is 47 Mb/s whilst running your Island 9524-0220-6933. When on Android Match Making opens with 250ms and finally down to average 76ms only one other person for party. Jump to Fortnite PC opening 125ms failling back to 66ms Ping. The red wifi tag warning on all the time for first five minutes 25 seconds match making on Android. 32 seconds on PC. **what is the networks ping for the accounts when the failure takes place? Easy to record as there is usually a large lump up to 250ms, before problem and the wi-fi red button** Mic/Voice is block on my session No one else on the game, but why is this ping of 77Ms average and often 90 Ms. Obviously BR is running at 10ms in comparison my region is Europe London servers are 40 miles away and most stuff is fibre/digital voice. The red Wi-Fi networks don’t appear on BR game on PC. ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 17, 2025, 5:36pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/5 "2025-06-17T17:36:03Z")
@Jimbohalo10 thank you for taking the time to test with Android and PC device. 1. We’ll investigate the Mic/Voice issue, I thought this should be enabled. Thanks for pointing out the ping, interesting that it stays for multiple minutes in red. On my sessions, it’s high at the start due to the loading. This usually is for 25-30 seconds, after that it’s back to normal. I’m working on rewriting the loading part, we should avoid having the ping spike at all. Regarding the join problem, when it’s happening the ping is normal, usually just around 40. The interesting thing is, we sometimes have some ‘spikes’ where the server appears to be hanging when we have 8 players. With for example 3-4 persons, it barely happens. But even if the whole lobby leaves, after this ‘game instance’ is glitched, with 1 player left, no one can join anymore. This one player left can play with 0 lagg, no spikes, everything completely normal and functional. We’re now in the process of slowly removing devices, and re running tests as well, to see if it is happening in one of the devices I coded or outside of it. Any tips / suggestions are definitely welcome! Thanks. ---
**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\ **Post date:** [June 17, 2025, 7:37pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/6 "2025-06-17T19:37:54Z")
> [@thrax207](#): > > We’ll investigate the Mic/Voice issue, I thought this should be enabled. Nintendo Switch 1 is the fastest at 93 seconds for everything 12 seconds to Match server. Second time round really quick There are no ping/FPS stats on a Nintendo Switch 1 This may be my settings but no music no voice on Android. If you want this on console somehow you have to get a visible message to say that the voice is off, seen that sort of thing on another island, possibly in Verse. Thanks for giving me a run down on whats happening. When the failure occurs Find PC delete all the logs del C:\Users%USERNAME%\AppData\Local\FortniteGame\Saved\Logs\*.\* open FN in lobby ```auto notepad C:\Users\%USERNAME%\AppData\Local\FortniteGame\Saved\Logs\FortniteGame.log ``` delete all the text. Open the island and hopefully only the matchmaking logging will now been listed put after failure twice put ===== END MATCH MAKING===================== When FN runs down everything after the label will be save and not really useful. Now we can grab that and upload to this or PM me the log. this log is of another island failing matchmaking every time [FortMatchMakeError3815-8254-6961.txt](https://forums.unrealengine.com/uploads/short-url/rOWkgCTcqmC01xJLazfpBP7O7oJ.txt) (119.3 KB) The log seems unusually difficult to understand over 50 pages with lots of unrelated errors ---
**Author:** ![BrendannnD](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@BrendannnD](https://forums.unrealengine.com/u/BrendannnD)\ **Post date:** [June 18, 2025, 8:00pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/7 "2025-06-18T20:00:46Z")
Also running into this. If you find a solution please @ me and let me know! ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 19, 2025, 8:15pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/8 "2025-06-19T20:15:44Z")
### **Summary of 3-Day Debugging Session** We have been testing this issue extensively over the past **three full days** , documenting every single test run and behavior observed. The bug we’re encountering is extremely inconsistent and difficult to isolate. We began by removing two major custom devices containing extensive Verse logic. After doing so, the issue appeared to be resolved — the map ran for **1.5 hours** without any joining problems. Encouraged by that result, we began reintroducing one of the main devices and started **removing logic step by step** inside the `OnBegin` function to pinpoint the problem. It **looked promising** at first — previously, the issue would occur after **30–40 minutes** if we are in the map with 4 players, but with some code disabled, it seemed delayed. However, after we thought it was finally resolved (and that we found which lines could potentially delay it), the bug returned again — this time after **1 hour and 30 minutes**. This delay-based failure is incredibly confusing. Disabling certain code **doesn’t remove the bug** , it just seems to **delay** it. We also noticed that the bug **appears noticably faster with more players** (e.g., 8) than with fewer. At this point, we’re not even confident anymore that deleting our custom devices guarantees long-term stability. We can not rule out the possibility that the bug still exists and possibly would appear even after **4+ hours** , this is something we might also test. Normally, I’m all for debugging and testing on my own — that’s what we’ve been doing, **12 hours a day** for the last few days — but I’m honestly starting to lose hope that this can be solved without **direct support from the UEFN team**. We’ll keep testing more scenario’s and keep you up to date. **Update:** I changed two small things before I went to sleep: 1. I removed some PlayerJoin / PlayerSpawn / PlayerLeave handlers, which had minimum code 2. I removed my 8 old spawn pads and placed 1 fresh one back This was active with 2 players for minimum of 10 hours. In the morning, I tried to rejoin with Player A, which was in this lobby for 10 hours. I received the following **NEW** error, **Matchmaking error #2.** I have attached the log. A fresh account was able to join this lobby without any issues. What completely confuses me is that the test I did without these 2 minor changes, resulted into the bug appearing after 1h30m. When I really look at the code I disabled after, it should not have had any impact at all.. [FortniteGameMatchmakingError2.log](https://forums.unrealengine.com/uploads/short-url/hn0hlssesjr8lmz0dZjS5RUHvX.log) (2.7 MB) ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 21, 2025, 2:05pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/9 "2025-06-21T14:05:44Z")
We’ve done a lot more tests, still keep running into the same issue. Now it appears around 40 minutes of playtime with 8 players. We have tried island settings with teams: 1. FFA 2. Cooperative 3. Team index 4. Custom All did not appear to have impact, kept running into the same issue. We have tried the following spawn methods: 1. In air (no spawn pads) 2. With spawn pads 3. As spectator (then later spawn them as normal players with respawn) Also did not have a positive impact. We’re running out of idea’s what to test at this point. Before we were able to test and reproduce within 15 minutes, now it takes 40 minutes with same amount of clients (8) Our game session is stable, low ping, no lagg, yet no one can join anymore.. @Flak @sonictke we’ve been digging into this for days and at this point, we’ve likely hit the limit of what we can debug on our side.. We’d really appreciate the teams help to move us and many others with matchmaking errors forward. Another big creator @BrendannnD also has this error with many of his maps, and it’s really impacting his numbers as well. ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 23, 2025, 11:59am UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/10 "2025-06-23T11:59:08Z")
Update: We’ve continued to test the full weekend. 1. We’ve ruled out verse persistence is not the issue, completely disabled it and no issues 2. We do have a feeling that something builds up overtime, but there’s no lagg in the game, so it doesn’t really look like a memory leak but can be. Very hard to rule out exactly what builds up here. Any idea’s are still welcome.. ---
**Author:** ![Flak](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/flak/32/769441_2.png) [@Flak](https://forums.unrealengine.com/u/Flak)\ **Post date:** [June 23, 2025, 12:01pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/11 "2025-06-23T12:01:17Z")
Thank you for the report @thrax207 - we have some folks looking into this. ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [June 23, 2025, 12:14pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/12 "2025-06-23T12:14:25Z")
Thanks a lot!! We really appreciate it. Some notes for the developers/testers regarding reproducing: 1. The current session, make sure to use 1 client to join & start the game. (important, there’s a small bug in our code which teleports the ‘Join game’ buttons too high with multiple clients) 2. After that join with the other clients 3. Make sure to claim the base on each, without claiming the base it’s slower reproducable / not reproducing perhaps at all. (We’re still investigating this atm). On join sometimes you stay in the ‘spawn’ area, please use the button ‘Join game’ & then walk over the claim base pad If you claim all 8 bases, we notice it’s now reproduced in like 15 minutes. Please let us know if you need any clients for reproducing, we’re happy to join on short notice. Also happy to hop on a call to explain if it helps. ---
**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\ **Post date:** [June 24, 2025, 5:18pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/13 "2025-06-24T17:18:20Z")
hi @thrax207 , The message has changes in the new 24 Jun 11:30 GMT update ![save9524-0220-6933CrashAfter35minutes](https://d3kjluh73b9h9o.cloudfront.net/original/4X/7/6/4/7644d789f5df5a0a90f054121d87b18c77db450c.png) ---
**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\ **Post date:** [June 24, 2025, 6:39pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/14 "2025-06-24T18:39:30Z")
hi @thrax207 , Turned off Sleep in Environment to Never. Then able to play for 72 minutes, Shot up everything The Ballon ship flying past does not take damage ![StillRunnin72minutes9524-0220-6933](https://d3kjluh73b9h9o.cloudfront.net/original/4X/f/e/f/fef627e32cfe0500e876087928e8d1051f6ce616.jpeg) ---
**Author:** ![thrax207](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@thrax207](https://forums.unrealengine.com/u/thrax207)\ **Post date:** [August 3, 2025, 7:51pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/16 "2025-08-03T19:51:10Z")
MAJOR UPDATE WITH ‘FIX’ @Flak we finally figured out what went wrong, this is HUGE since I found also a problem in parallel for Scene Graph. 1. In normal (non-scene graph) maps, if you create more than 8000 material instances, the lobby gets in this glitched state. It doesn’t matter if you ‘throw’ away the material instances, they never get garbage collected somehow. You can try this with very simple code in the OnBegin, @editable CreativeProp : creative\_prop = creative\_prop{} OnBegin():void = loop: Sleep(1.0) for (X := 0..100): # Create material instance and set it on the creativeprop Material := NewMaterial{} CreativeProp.SetMateiral(Material) 1. In Scene Graph, the issue is similarly replicated, but then even with normal materials, since you always have to initialize them. (Basically keep creating materials and set them to the creative prop) 2. ON top of that, Scene Graph Entities have the SAME issue with not being cleaned up properly. (Not sure if it’s garbage collector). - Create new entity with a static mesh - Add entity to the main entity (Device#GetSimulationEntity) - Remove entity using RemoveFromParent You will see the entity is properly removed, yet if you do this many times like 8k plus, the game becomes unjoinable. 1. I tried to bypass this issue from #3 by ‘reusing’ the entity, and removing the Static Mesh component using RemoveFromEntity on that static mesh component, and then adding a new static mesh. However, if you create enough static mesh components (probably around 8k as well, NOT sure about this number so please test until like 50k or something to be sure) , the same issue appears. All 4 ways lead to the join being playable when you’re in it, but when you try to (re)join that session, it is impossible. Always network connection lost. ---
**Author:** ![Gustavo\_UEFN](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Gustavo\_UEFN](https://forums.unrealengine.com/u/Gustavo_UEFN)\ **Post date:** [August 20, 2025, 4:25am UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/18 "2025-08-20T04:25:10Z")
So we cant do anything about it? ---
**Author:** ![Bug-Reporter](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/bug-reporter/32/997076_2.png) [@Bug-Reporter](https://forums.unrealengine.com/u/Bug-Reporter)\ **Post date:** [October 9, 2025, 10:12pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/19 "2025-10-09T22:12:53Z")
FORT-925424 has been ‘Closed’. This issue won’t be fixed—please see examples of why this may be the case. ---
**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\ **Post date:** [October 10, 2025, 5:00pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/20 "2025-10-10T17:00:25Z")
> [@Bug-Reporter](#): > > This issue won’t be fixed—please see examples of why this may be the case. Hi all, Used Google AI to see what these possible examples are **Reasons an issue might not be fixed** Epic Games does not publish a list of unfixable issues, but based on player reports and development practices, here are some common reasons a bug may persist: - **Resource allocation:** The development team must constantly prioritize fixes based on impact and player count. The vast amount of new content, game modes, and seasonal changes means that bugs that only affect a small number of players or a less popular game mode are often pushed to the back burner. - **Technical complexity:** Some bugs are technically difficult or time-consuming to fix. Resolving them might require a substantial amount of work and testing, which can delay the release of new content. For example, some Creative mode physics bugs may be deeply rooted in the engine. - **Moving on to new content:** _Fortnite_ operates on a tight seasonal schedule, with a constant push for new features and cosmetics. Some players believe Epic intentionally ignores older bugs to focus on producing new, profitable content, leading to a “bugfest” as new issues stack on old ones. - **Third-party or hardware-specific problems:** Crashes and errors can sometimes be caused by external factors beyond Epic’s control, such as outdated graphics drivers, software conflicts, or hardware limitations on the player’s end. In these cases, the developer can only offer troubleshooting advice, as the root cause is with the user’s system. - In the future these could become - **Known and communicated issues:** On the Epic Games Community Issues page, you can see a list of known issues. Some bugs are listed as “Investigating” or “Cause identified & fix being worked on,” indicating that the developers are aware of the problem but haven’t deployed a fix yet. In these cases, the fix is coming, but not immediately. ---
**Author:** ![system](https://d3kjluh73b9h9o.cloudfront.net/original/4X/7/1/3/713c9d3f58553f0de89543d76a8a3a2779dc9fa4.png) [@system](https://forums.unrealengine.com/u/system)\ **Post date:** [December 14, 2025, 1:42pm UTC](https://forums.unrealengine.com/t/critical-tycoon-unjoinable-network-connection-lost-after-15min-matchmaking-still-sends-players/2562223/21 "2025-12-14T13:42:14Z")
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