Well, probably contact them via email is an option but still a vague idea I guess. I think before you engage in some online casino you should check it first if they have bad reviews or something, find out if they have an issue on payment. Personally, I am currently in bitcoin casino and I do check it first if there's an issue but I find out some of its features that it has Live Chat, Email support 24/7, Low deposit options, Fast withdrawals, SSL encryption and so far they never fail me. I am full of myself that it is reliable one based on my experience I had in this bitcoin casino.