If you want to re-register for Azure multi-factor authentication and use Authentication app on a new/existing phone, follow these steps;
Login to Azure Portal -> Active Directory -> Your user account –> Profile
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Click on Authentication methods link.
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Click on Access Panel Profile link. This will take you to your profile page.
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Click on Additional security verification link.
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Select this option to view QR coce;
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You are ready to restore your credentials.
Resources;
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