Ok so I was playing halo reach and I got a into a game lobby with some people and they say to put a controller in so I did.and after a few matches they told me it was a boosting. game and I didn’t know and I’m really really really sorry about that I’m not gunna lie and say I didn’t but I didn’t know what they was doing at first can you all pleases unbanned me I never cheated before but if 343 reads this can you I won’t ever do something like that again I never did in my life.please I love halo I have halo 4 Legendary pack pre order and if you can please unbanned me thank you.and my gamertag is APEX PREDAT0R10
This thread is relevant to your situation, I suggest you post there. 
Why did I get banned? The Official Thread