Sign in without phone for work

Dear antoine grand

When an organization enables MFA (Multi-Factor Authentication), the available sign-in methods—including whether you can use a personal device or an alternative option are fully managed by your company’s IT or Azure AD administrator. Because of this, the fastest solution is to request an MFA reset from your IT admin so they can remove the old Authenticator registration and allow you to re-register using a method approved by your organization.

If your company allows it, your admin can also enable additional MFA methods such as hardware security keys (e.g., FIDO2), SMS, or a work-managed mobile device, so you won’t have to rely on your personal phone. Once the admin performs the reset, you should be able to sign in again and configure a new verification method that meets your privacy and policy requirements.

I know that using a personal phone for work authentication may not be acceptable for you, and this is a common scenario that organizations can easily address through proper MFA configuration. Please reach out to your internal IT support and request an “MFA reset for Microsoft 365/Azure AD,” and they will be able to resolve it quickly.

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