Banning help

Hi Guys, Me and my sister have been playing Halo reach for years know and we recently gave our 360 to my friend during our extremley prolonged move, but luckily we just moved in and got our console back but unfortunately he somehow managed to get the whole console banned from JUST playing online halo reach. We’ve tried to contact xbox live but they sent us here to the forums. If anyone could help we would really appreciate it! Thanks

Your friend modded armor and/or credits on one of your accounts, end of story.