How to access my own cPanel for the host domain

[bunhosting]

Very noob question, but I'm very new with WHM/cPanel.

My question, i have access to WHM (My own hosting server) but I can't seems to have access to my own cPanel for the same host.

I can't logon to cPanel using my root username/password.
If i logon to cpanel using root username and password i get this message:
Internal Server Error

Could not fetch uid or gid for : root

I want to add a database and upload my web site.

[bunhosting]

Another message,

"Create a new Account
Account Creation Status: failed (You cannot setup a domain that is the same as the servers hostname )

You cannot setup a domain that is the same as the servers hostname"

[bunhosting]

I figured it out, changed host from myhosting.com or 123.myhosting.com