I'll get straight to the point, Me and my friends are playing a 3 player multiplayer game. Me and one of my friends both tried to send an alliance request request at the sama time and broke the diplomacy. Neither of us have any problem with other players (Ai or player) but we can't send any proposals to each other, It won't even consume our influence!

By the time we figured out about this we had already progressed about 35 turns and the save was deleted, so any help from a game dev or experienced 4x player would be appreciated.