multiplayer disconnect when using r key

yo! please help. playing duo with friend, both tried to host and nothing changes. when holding R/use R key item/going to a victory lap we are disconnected from each other. sometimes disconnect happens instantly, sometimes in several minutes of playing since the run restarts. is it possible to fix? we both have stable internet, literally sitting in the same room and using the same wifi. other coop games work correctly but not isaac. and disconnects never happened when we just played without restarting the run