The information I have says that 1xBIT bookmaker is anonymous and does not require KYC verification. To confirm this, I will quote another user who claims to have used services of this bookmaker without data verification:
I’d rather fill up the KYC form that to use a scam site which is 1xBit, better to avoid this site at all cost.
Or just do some good research before you register at any casino. I always do that before I deposit any money. However, when it comes to anonymity, 1xBIT is known not to reveal any information about its players.