There is some explanation to this, I suggest everyone reads the T&C as it is a thing that you must do, and it is true that the casino doesn't have any obligation to explain what was actually happened. There has been a lot of bigger wins than the amount mentioned here and all is good.
Well ok, they probably have points in their T&C allowing them to behave this way, but what would you do if you were me? Just shrug your shoulders and acccpet that they took all your winnings because the terms allow them to do whatever they want? I want to at least try to get my funds back, especially since I have no clue what I did wrong.