I am not siding with Rollbit or anything but from what I have seen they only flag accounts if they find something. I am sure you've been asked by other forum members whether you have used a VPN, you used someone else's device to access your Rollbit account, someone other than you used your device to access their Rollbit accounts, etc...

anyway, from the looks of it, holydarkness is already tackling your issue with Rollbit, that guy has a track record of helping gamblers fix issues with casinos.