Hi @Édouard Reid,
Thank you for contacting the Microsoft Q&A Forum.
Based on your description, it appears you're unable to sign in to your Outlook account because the Microsoft Authenticator app is prompting you to enter a verification number but you're already inside the app and no longer see the window where this number can be entered. This issue typically occurs when switching to a new phone without restoring the Authenticator backup.
Here are recommended steps you can try:
For personal Microsoft accounts:
Use the recovery form: https://account.live.com/acsr Please provide as much accurate information as possible to help verify your identity.
You may also contact Microsoft via phone: https://support.microsoft.com/contactus
Alternatively, use another personal account to create a support ticket: https://support.microsoft.com/contactus
For work or school accounts:
If you're a regular user, please contact your Global Administrator and ask them to follow this guide to reset your MFA: https://learn.microsoft.com/en-us/entra/identity/authentication/howto-mfa-userdevicesettings
If you're the only Global Administrator and locked out, please contact Microsoft Support by phone. The support agent will escalate your case to the Data Protection team to help you regain access.
We understand how frustrating this situation can be and truly appreciate your patience. Please don’t hesitate to reach out again if you need further assistance. We’re here to help.
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