"Server Disconnected"

[HarkeymanOG]

So basically what keeps happening is I keep tryna play some zombies with my friend and we can play 1 game and everything is good but once we die or whatever and we go back to lobby to start a new match and then once I press start game it says what the picture said that I put and then it will kick my friend from the lobby and then well both have to restart our game n stuff just to play again it's just a inconvenience to have to do every time tbh any solutions?!