Took my money based on unjustified violation of non-existing term

I have a problem with the above website, www.expekt.com. A few days ago, I have placed a deposit on their website and used it in the Live Casino, on the Roulette(but only on Live Casino). This resulted in a winning of approximately 80000 EUR. Obviously, I have tried to withdraw that amount and here is where the problem started. I haven't received any email from them regarding the withdrawal, and today I had the surprise that my account was blocked with no reason and with no notice. I had already tried to talk to them regarding this matter and all they are saying(in the live chat) is that I have to wait for them to perform a security check. The problem is that they don't give me a timeline for resolving this verification or any other details. Another thing is that this is not the first time I withdraw money from them and they never had to perform any security checks. The only difference is that this time it is a large amount of money and I feel a little hijacked. I have already provided them all the identification documents(credit card, driving license, my ID card, bank account statements) but still no answer. All I get is that I have to wait. More than this, one of their Live Chat agents told me this is the first time this is happening so this is another reason I am feeling hijacked.
I hope that you can help me resolving this issue. I have all the confidence in you! Also, if you require further details or documents, please let me know, I will provide anything immediately!
Thanks in advance!
Cosmin