First of all: No, it is not.
I have already deposited bitcoin worth hundreds of dollars, wagered it and withdrawed BTCback to my private wallet without any problems, so the problem must be with your account. Have you contacted support? They usually reply very quickly and can certainly give you more detailed information about why you are getting the error message and how you can fix it.

As an additional request: A scam accusation is no small matter when money is at stake. Please only make such accusations if all other reasons for something not working have been ruled out. Otherwise, other users may come across your post via Google search, for example, and actually believe it.