Option of create multiple accounts for each identity provider not working as expected in Firebase Authentication

As you can see in the image below, I enabled the second option (Create multiple accounts for each identity provider)

Now this email m6454611@gmail.com is already in Firebase Authentication and I already logged in using Google provider.

I want to create a new account with the same email in the above but with the email provider but it tells me email account registration unsuccessful. It will work without any problems if I delete the email that signed in via Google provider.

I expected it will create the same email without any problems because it is a different provider

Did I misunderstand anything?

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