Click the "Manage in G Suite Admin Console" next to the domain you want to do it to.
Under "Status" column it should show you who your domain is registered under.
An example for mine was under Enom (Yours may be different) in the status column so I Google searched and found the link for them. https://access.enom.com/
Once you login you can access your Cname.
I will update and let you know if implementing the fix worked for me.