Can't create cPanel account in WHM usermeta

Hello I am getting the following error when trying to create a new cPanel account through WHM. I am simply trying to get access to our cPanel and FTP so I can upload the new site. Account Creation Status: failed

(XID 2ub23g) The domain "domain.co.uk" already exists in the userdata.

Any help is greatly appreciated. I am not too familiar with the technical details of WHM so please explain in simple terms if you are able to help :) Thanks!