Most of the things that I have read in some betting sites is that they weren't able to withdraw their winnings because of the Terms of Service being violated which is valid in their part.
What I think about your situation is it's about registering again. Even though you have registered before, your info is in a country that's not allowed. Probably another account? But this might violate another rule again. Take care OP.
I think many of us are aware of the rules of our country but we also know that enforcement is quite lax. If I and many thousands of players at this forum obey the laws of our country with digital currency we would not even be allowed to own any crypto.
BUT I agree, be as safe as possible and if a platform does not accept your nationality,,, no need for to push the issue and move on to another one. Many of the sites on this forum with ANN thread allow your country, if you just check.