I assume you log in and send support a message with details etc. If not try the 24 hr live chat facility.

so is it for sure that we are going to get our rank back because i was 6th level 20 some and the same thing happend to me, i joined this guys party and he said watch the video named "Modz" so the vid was at dome and they were playing search, so he told me to fast-foward all the way then join his game..... when i joined his game he told me to beack out because there was something wrong with the connection, and when i backed out my screen was frozen and i was level one.

and this is why i dont join ANY private matches...

@G IH A IN ID II I joined a lobby and watch a video in his vault and i got deranked but i called activition and they said i will get reset back but nothing happened

I was in a public match like this on CoD4 back in the winter. It was FFA and when I joined there was all this wierd text on the screen like "Derank" "Take XP" or something like that and all the text was red. I backed out immeditately and nothing happened to my rank. So strange how hackers mod so easily to this day on XBL. It's been out for what? 6 years now and they still can't ban hackers.