Redirecting to old tenant

Hi @BNI

Thank you for posting your question in Microsoft Q&A. 

Based on your description, this issue may be caused by outdated credentials on the user's mobile device or a misconfiguration following a tenant migration. 

You could try to follow these steps to troubleshoot it: 

Clear App Cache on Mobile Devices.

The app may retain outdated login credentials that don’t automatically update after tenant migration. Clearing the cache could help reset these stored details. 

Reinstall the App.

Uninstalling and reinstalling the app ensures a clean setup and removes any lingering configuration issues. 

Remove and Re-add the Account.

Ask your users to completely remove their work/school account from the app, then add it back. This refreshes the authentication and syncs with the new tenant settings. 

Check Microsoft Authenticator configuration:

Open the Authenticator app. 

Make sure the account for the old tenant is removed in their MFA application. 

Re-add the account for the new tenant. 

To address your issue more effectively,  could you please provide more details for the following question: 

Is this issue affecting all users in your tenant? If yes, you could ask your administration to recheck any Conditional Access Policies that could be affecting user access. Additionally, they might consider revoking old sessions, which forces users to re-authenticate and can help resolve lingering access issues.

May I know if there has been a recent tenant migration or domain change? 

Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution. 

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