Confusing Login Flow After Changing Email on Google-Authenticated Account

Hi everyone,

I wanted to report a confusing authentication experience that may be worth reviewing from a UX / identity-flow perspective.

Scenario:

• Account was originally created using Sign in with Google

• Original Google email: example@gmail.com

• Later, account email was changed to a custom domain address: example@customdomain.com

Observed Behavior:

After updating the email, the login flow became ambiguous:

  1. Attempting username/password login resulted in a message indicating that I must sign in using Google (expected, since the account was created via Google).

  2. Attempting Google login with the original Gmail account triggered an account creation flow, followed by an error stating that the email was already associated with an account.

  3. Attempting one-time code login using the updated custom domain email still resulted in the same “must use Google login” message.

  4. The only successful resolution was creating a new Google account using the updated custom domain email and signing in via Google with that account.

Why This Was Confusing:

From a user perspective:

• The system did not clearly indicate that the authentication method remained locked to Google despite the email change

• Error messages implied conflicting states (account exists vs account creation flow)

• One-time code login suggested an alternative path but still redirected to Google enforcement

Suggestion:

It might help to provide clearer messaging when:

• An account was created via SSO

• The email is changed to an address not previously tied to that IdP

For example:

“This account was created using Google authentication. Please sign in with a Google account that controls [new email].”

This would have made the resolution path immediately obvious.

Impact:

No security issue observed, but the flow created significant confusion and temporary lockout anxiety.

Im having this issue right now, is there a ix?