Losing connection to my fireteam

I’ve been experiencing a problem where I’m in the middle of loading up a game with my friends and then after a few minutes I’m kicked out of my fire team to the main menu saying “Left Fireteam” and I’ve experienced this problem all day so far. I’ve hard reset my XBOX, tested my multiplayer connection and checked if my NAT was “behind the cone” and it was, I’ve reset my router and modem, restarted the game, and even unplugged the XBOX power brick from the console and the wall for five minutes and nothing has worked so far. I’ve tried loading up co-op campaign missions and then I’m abruptly kicked back to main menu saying “Left Fireteam”. Is there a server issue right now or is there anything else I can do to resolve this issue.