Add subdomain for other domain than main domain

i add domains like
Main - something.com
Subdomain - 1.something.com
                   2.something.com

everything is fine but when i add another domain like
Domain - everything.com

when i try to create subdomain of everything.com

Add SubDomain >> there is only main domain in the menu please tell me ho can i add subdomain of everything.com

Thank you

Hi are you logging in as root user to CWP or are you logging into the user panel ? also when you add domains are you adding it via a new user for each domain ?