Sadly my friend it looks like nothing can be done about it. Chances are someone reported you via in the in-game report function and the powers that be decided you did something wrong and reset you. Have you checked your e-mail for elite or anything like that? This is strictly a what if case though, have you done anything that could be considered boosting or anything that could seem like you are having an advantage such as lag issues? The CoD community is so try-hard at times that when anything doesn't go their way it's always you are cheating or boosting as even some on this forum have claimed with diamond camo.