Firebase Auth(Google Sign in) Is returning null as email address!

[calicratis19]

[REQUIRED] Step 2: Describe your environment

• Xcode version: 11.1
• Firebase SDK version: Latest Release(Installed from pod)
• Firebase Component: Auth, Core, Database, ML Vision
• Component version: Latest

[REQUIRED] Step 3: Describe the problem

Starting from last 12 hours or so the firebase auth is returning null as email address. Its returning name and UID correctly. The API call is below
Auth.auth().currentUser!.email

Steps to reproduce:

Try to sign with a new user using firebase auth. If the user signed in before then delete it from firebase authentication table and try again.

####What happened? How can we make the problem occur?
The output of the mentioned API call is null. This is impacting both ios and android.

This is impacting us pretty badly. No new user is able to sign up now. Please check it URGENTLY!

[google-oss-bot]

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[calicratis19]

We have found the problem. It occurred due to "One account per email address" settings change in the firebase auth settings. We set "Allow creation of multiple accounts with the same email address" as enabled which result in the mentioned error. IMO it should be specified in the settings page that this error might occur if the settings is changed.