before right? When it first happened? Were there any purchases at that time? I'd suggest getting another card issued to you via your bank but M$ should at least remove the charges and the bank and them can sort it out.

Every person there has a limit as to how much they can do so if they say it's past their limit have them (don't get transferred) and their boss work out something agreeable.

They will work it out you just have to stay focused.