Accidentally created new account?

So here’s the thing, I use google to sign in to gitlab and recently created a new google account which is now my primary account.

I just tried to sign in to gitlab with that account because I couldn’t remember, that I had not done this before with the new account. When I landed on the “agree to our terms and stuff” page I noticed my error and clicked “decline and sign out” with the plan to just check if I could change my name and email on my old account which would be better anyway.

So I logged in with my old google account and tried to change the email but got an error “email already taken”.

What do I have to do to be able to log in with my new google account and keep all my projects?