How much did you try to withdraw? Which games did you win on? Is it possible that you had an account previously opened with them? Sometimes they are very strict with multi-accounting. I would suggest emailing them and being patient, I'm sure they will help you out as they have a fairly decent TrustPilot score. If you did nothing wrong, you deserve to be paid. Especially if you lost many deposits before, this withdrawal should not be an issue. I think you should include more info in your post and include some screenshots in order to get the best help and support!