I am not able to sign in authenticator and teams in my new mobile

@Mano Dayalan Thank you for reaching out to us, As I understand you are unable to sign in to teams as authenticator app is registered on the old mobile device.

If you are normal user (not the admin) - you need to reach out to the Global admin of your tenant to re-register mfa - https://video2.skills-academy.com/en-us/entra/identity/authentication/howto-mfa-userdevicesettings#:~:text=Require%20re%2Dregister%20MFA

• Require re-register MFA deactivates the user's hardware OATH tokens and deletes the following authentication methods from this user: phone numbers, Microsoft Authenticator apps and software OATH tokens. If needed, the user is requested to set up a new MFA authentication method the next time they sign in.

Reference: - https://support.microsoft.com/en-us/account-billing/common-problems-with-two-step-verification-for-a-work-or-school-account-63acbb9b-16a1-47b9-8619-6a865e8071a5

If you are only the admin of your tenant, you need to contact our support via - https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 where you need to work with our data protection team.

Refer to this QnA post - https://video2.skills-academy.com/en-us/answers/questions/1455267/global-admin-account-locked-unable-to-access-entra for account lockout scenarios.

Let me know if you have any further questions, feel free to post back.

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