Hi just last night I joined a server and my rank was deranked and my xp went negative 158000. So I called activision and they contacted Infinity Ward who handles the online play for the game and they reset my rank as well as my xp so that I can continue to play the game. So I just wanted to let everybody know that if this happens to you DO NOT FREAK OUT LOL because fixing this is only a phone call away and about a 24 hour wait to have it fixed. The only irritating part was being on hold with activision for about an hour to finally talk to someone. The phone number can be found on the back of any activision game book or just simply google as i did.