I just finished playing a game of Arena: SWAT and as it loads the screen where it gathers players, I get banned… wtf? I don’t get how I’d get banned for playing the game.
It was the DNF prior to that match. Although, 1 DNF in over 6 months doesn’t seem ban worthy
There’s a sticky thread for this. Go there. This is going to get locked
Please use the ban thread in the support forums for further help 
Official Halo 5 “Why was I banned?” thread