really hard to connect people together

I have on many ocassion have trouble keeping parties together in the game. so many times if people accidentally press b they leave and can’t rejoin unless they restart the game or xbox one all together. Many times i have also invited people and it says promote to leader and they arnt in my game at all. i have had to restart the game at least 6 times today just in order to connect to friends and honestly i have hella supported this game to no end i mean its killing me inside. i can take bad matchmaking and slow connect time but it seems as if this game cant complete simple task in which all the previous games on the 360 still easily complete with ease.