I’m really upset. First my rank reset from 13, and now it reset after winning a match on Shrine that should have put me at nine. I think I’m gonna go burn this game and go buy Call Of Duty??
I’ve had it once. Was level 16 and after a loss I was back at 1.
I quit halo and went to my account on halowaypoint. It still said I was level 16. So I restarted Halo and there it was back again: level 16.
Those rank resets are just little bugs. They don’t hard reset your rank, it only appears ingame.
Simply restart Halo and you are good to go 
343 please restore my rank I was a level 10 (add or subtract my level in addition to recent games I played), I don’t know if I can even rank up. my nephew and I were playing and he ranked up 3 times and I stayed at a level 1 and I did better than him and we were on the same team.
mine just reset from 7 to 1 and i won the match to boost me up. Reset the game and it still says one. What the heck!
I have had my rank reset probably 4 times. the first time i had to start from 1 again, the next 2 i played one game and my rank went right back to where it was before. This last time though… rank didn’t come back so im starting from scratch again 
i think the ranks shown on waypoint are the highest rank you have ever achieved.