You are going to find very little help if any at all. The problem lies in if that casino suddenly disappears, or you have a big when and don't get paid.
It is, however, illegal for them to accept US players but there is little that can be done to stop it. It is not illegal to wager with unregulated casinos based offshore. What if the Online Casino is not State Regulated To see if there are state-regulated online casinos where you live, take a look at our guide to legal online casinos.
Playing on a state-regulated online casino is the safest option to ensure your deposited money is safe and you get paid when you win big.