This is to cheat on sports betting. When something like this happens, the casino has to react. The consequences obviously do not please those who create that accounts.
Anyone with a half-decent brain knows that 1xbit comes up with these lame excuses regularly in order to avoid paying players their winnings. They just return the deposits in order to look legit.
You can't prove these are excuses. In my opinion, you are wrong and therefore resolving such a conflict in the form of a deposit return is the best solution.
Did you register at 1xBit at all, or are your accusations based only on that someone wrote something?