Excuse me if my English is a bit twisted.
So, I explain, my xbox live account is associated with my facebook account. I used to play with my facebook account rather than with my windows account. Only, here under Modern Combat 5 blackout, my xbox account has been associated with my brother's facebook account. So I wanted to erase my progression on xbox live, so I followed the method of microsoft, except that in my xbox account the part delete does not exist. I can not reset the game and my progression has become my brother's progression.
So I would like to know how to reset the game or completely erase xbox live and start a new game with this time my associated accounts.