Why is everything in the main character running 2 times in multiplayer?

I’ve got a strange problem. I added multiplayer features to my game, and suddenly everything in the event graphs begin to run for 2 times with more than 1 players. I’m using a dedicated server. One event graph is totally usual, the other one does not have a player controller assigned.

Event graph (part) of thirdPersonCharacter:

Blueprint of chatbox widget:

Can anyone please help me with this? I can’t let the chat box being printed 2 times, and I have to check and choose the pawn with a playerController to get the replication done.

It’s probably the case that you see two player characters on the screen. Thus, there will be two invocations of the player character event graph.
The one without a player controller is the remotely controlled one you’re seeing on your local machine (the other player.)
In the Blueprint debugger, there is an instance picker popup in the top center of the screen where you can focus on a particular instance if you want to debug only that.