Im banned from auction house

I just got back from over seas and i jumped on my Xbox to play forza 4. I go to the auction house and then it says this account is banned from this feature. So my cousin or brother has got me banned and i don’t think its fair. Please try sort it out because i love this game and i want to buy and sell cars.

Your sincerely
MystiCTiGeRM8 (Cory)

We are each responsible for the play under our gamertags and is published in games from the Xbox Live account. They did you no favors by the misuse of your account, starting in September, 2014, and continuing through January of this year when illegally modified cars were posted for sale under your gamertag on the Auction House. The January 4, 2015, attempted sale was the third and final step through the ban process.

No further discussion of your ban(s) shall be made on these forums. You may send an email to Turn 10 at You will receive an automated response, but that is really acknowledgement the email has been received.