but i mean, i'm logged in as admin, and im trying to a add a domain for a specific user X who already has a domain to his account. his plan allows for 3 in all.
the domain admin link ur talking about allows me to add domains directly to the admin account, not a specific user.
so click show all users from the admin tab, click the user name, click login in as 'username' then click their user tab and do it from there. That will add it to their account.