Firebase admin auth update user is not working

[Jean-Paul Abi-Zeid]

I have a web app and users have two ways to sign in, the first is using an email/password provider and the other is using google account. I am trying to implement a change email feature using the firebase admin sdk, and succeeded for the users that use the email provider however when changing the google account to another google account both old and new accounts can access the same account on my app instead of replacing the old account with the new one. Please advise.