This domain is already associated with this account "i*****o@e*****"

This domain is already associated with this account "i*****o@e*****"

I am the owner of this domain:  https://www.estatedraw.com , but when I tried to Sign up with this domain that I already own, it says This domain is already associated with this account "i*****o@e*****". I really am have no idea who own that. I want to set up an email address named support@estatedraw.com, which is under https://www.estatedraw.com that I own. Would you mind tell me who own that? It could be anything like: Email or Name.

Thank you in advance.