Game ended itself with no warning, sent back to Main Menu

Never posted here before. Was just in game with one premade friend and we were around 30 minutes into game. Then suddenly we started to lag and disconnect. When i pressed quit game in an attempt to retry the game it kicked us out as if we have not played a game. The play button in the top left is there and the game seems to not have happened. Was wondering if a bug anyone else has come across.