Hello Georgia Matragkou
As discussed offline, In Microsoft Authenticator, Microsoft Entra ID does not produce its own account tile. No new account appears on the main page when you add Entra ID because it adds sign-in methods (Passkey, MFA, Passwordless) to your current work account (PII@microsoft.com).
The "Account added" screen verifies that the setup was successful. The same Microsoft work account entry will be used for your Entra ID MFA.
And you were able to access Microsoft Entra as tested.
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