yeah, just confirming that signing in with your regular google account works. i was signed in with a youtube account that, when i went to the user selection page at the top was like username@google-pages-12312831823 or something. sign in with google account, remove that one, then i still have the choice to sign in under my real name, or the same youtube account but just called 'username'. remove the @google-pages-1231251231 and itll be back to normal
So Google changed some things and they didn't migrate correctly.
I have been signed in with both a long time (and 2 other accounts, my kids, using google.com addresses)
I ran I to this age issue. So signed out of my account. Google and brand. Signed back in and now the accounts are displayed differently.
The email address is listed then the account name and avatar under that. So both of my accounts are listed together where before they were not.
And now the age restriction is gone when selecting my brand account.
Why Google didn't just populate that way is beyond me. And the error message it was giving didn't really hint at it.
Plenty of room to say sign out of the brand account and sign in with goggle account again to resync brand account.