Stole my winnings without any explanation

I registered an account on Svenbet 17th of November. After reading all terms, I deposited $150 with a sports welcome bonus. I was lucky to win a couple of games, and ended up with an amount of appr $1300. After the welcome bonus was done, I played some more, and then asked for a withdrawal. I sent in all necessary documents, and they seemed to be accepted.

But suddenly I got an email saying they had confiscated all my winnings except for the €150 I started with "due to the following terms of our Terms & Conditions".

They proceeded to copy-paste an entire paragraph (!) that contained absurd rules about bots, exploitation of loopholes, fraudulent rake-back activity, personal bankruptcy and so on. I knew that I had done none of this, so I asked them several times to be specific, in showing MINIMUM ONE rule that I had broken.

They ignored it and proceeded to copy-paste the entire paragraph again several times. So I'm left with absolutely no reason or explanation at all. This counts as highly suspicious activity in my book and a completely arbitrary way to take honest people's fortunate winnings.

Stay away!