I cannot login to outlook on ios device as microsoft authenticator is not working.

Hi @James Quirk, 

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

This issue typically happens when setting up a new device because the new device's Microsoft Authenticator app isn't yet synced or properly registered with your account. While the app may show your email, it isn't able to generate codes until it's properly re-added as an authenticator device. 

• If you still have access to your previous phone, try opening the Authenticator app there. You may be able to retrieve a verification code or approve the sign-in request.   
• Use an alternative verification method: select “I can’t use my Microsoft Authenticator app right now.” This may allow you to verify your identity via SMS or email, assuming those backup methods were previously set up.  

If the above methods don’t work 

Scenario 1: Since your email is a business account and you're an end-user of your organization (not Global Admin – usually is your IT Admin), your company IT team or Helpdesk may be able to reset your Multi-Factor Authentication (MFA) settings. This will allow you to reconfigure MFA from scratch on your new device.  As general Microsoft Support, we do not have administrative access to change these settings. Only your IT team has the ability to adjust or reset your MFA configuration. You can also refer to this Microsoft support article for more information: 

For step-by-step details, see the official Microsoft documentation: Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID | Microsoft Learn    

If you’re unsure who the IT Admin is within your account's organization, you can find guidance on locating them here:  How do I find my Microsoft 365 admin? - Microsoft Support  

Scenario 2: In case you are the Global Administrator and have another Global Admin in your organization. Please ask them to follow the step in the instruction above to reset your MFA.

Scenario 3: In case you are the only Global Administrator and you are completely locked out from the tenant. You might need to contact us via phone service number: Customer service phone numbers - Microsoft Support. The agent will be able to create a ticket for you under the affected tenant and then transfer this ticket to Data Protection team who could help you to regain access.    

I hope this explanation helps you understand. Please let me know if you have any other questions or need further assistance.  

Looking forward to your response! 

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