I am trying to park domain.com, but it says this domain name is owned by another userThis error means that Cpanel finds yourdomain.com in the server's configuration files and cannot park it on your account.
Please try removing the domain from your account's Addon domains first. If you have another account with us make sure the domain is not configured on it either.
If the above does not help please log in your Customer's Area and go to Get Support -> Report hosting related issue -> cPanel related problems and report that your Cpanel is down.
