Unity Error Crashing Game While Playing Multiplayer Arena

[St4rSw0rd]

After I've joined a multiplayer game and am playing for some time, game will randomly display a message like "null instance not set to object" in white text briefly at the top of the screen before crashing to desktop. It does this after I've already been running around shooting people and it happens every time I join a game online, so I can't play. I hope this can get resolved as this game is amazing and I want to be able to play it.