Client Crash on Map Change


I’m having an issue when playing online on my project. When the map changes from lobby to a new map, the client crashes with an error:

Clients can connect to the lobby which uses a lobby controller and lobby gamemode. The server host then starts the game which loads a new map which uses a different gamemode and controller. This happens with both seamless and non seamless travel.

I’ve tried using the built in server sessions and advanced sessions with the same error. The host is a listen server and using Steam for online. I tried using console commands and the open level (server) nodes which no success. This error doesn’t occur when testing on my own PC with 2 game instances. The client can restart the game and connect back to host mid game fine which leads me to believe the transition from lobby to the level is the problem but I can’t tell what.

Any help would be appreciated.