"The domain name is not available for registration"


I have bought a domain name and updated the name servers as mentioned in the
documentation, now I’m trying to create a new account for this domain but It doesn’t
work and it always gives me this error

“The domain name is not available for registration.”

What is the problem ?

my domain name is “hexensoft.com

The domain name is already attached to the account with username epiz_20418016. If you want to use it on another account, you’ll need to delete it from epiz_20418016 first.