"new domain" button is missing. How to add one?

Hello everybody,

I’m currently testing gitlab.com to understand how comfortable is to manage accounts via saml. I need to disable email confirmation for new accounts, and according to manual it is possible for verified domains: SAML SSO for GitLab.com groups | GitLab

I try to follow the manual, however when I navigate to “pages” menu, there is no ‘new domain’ button, and I just don’t get what i’m doing wrong. Can anybody help me?