Someone is trying to log into my account using authentication

Unrequested Microsoft Authenticator prompts mean someone is repeatedly trying to sign in with the account username, but without approval or the correct second factor, they cannot get in. Denying or ignoring the prompts keeps the account safe, but the attempts can be reduced by changing how the account can be used to sign in.

Take these steps:

1. Keep denying any prompts not initiated by you
   For every unexpected “Are you trying to sign in?” or number-matching prompt, always choose Deny. Unrequested prompts typically mean:
   • Someone is trying to access the account, or
   • Someone mistyped their email/phone, or
   • A delayed prompt from a past attempt.
     Without the correct response, the account remains safe.
2. Change the sign-in email (alias) and disable sign-in on the old one
   If the current email address is known or exposed, attackers can keep triggering MFA prompts just by entering it on the sign-in page. For a personal Microsoft account:
   • Go to the Microsoft account page and add a new alias (email address) to the account.
   • Set this new alias as the primary alias (primary sign-in email).
   • Then change sign-in preferences so the old alias cannot be used to sign in anymore. It can still be used to send/receive email, but sign-in using that address will fail.
   • After this, when someone tries to sign in with the old email, they will get an error and will no longer trigger Authenticator prompts.
   This approach is described in the referenced answers as the recommended way to stop repeated unwanted sign-in attempts while keeping the account secure.
3. Review recent activity and security settings
   • Check the account’s recent sign-in activity to confirm that no unauthorized sign-ins have succeeded.
   • If any sign-in looks unfamiliar, follow the guidance to secure the account (change password again if needed and review security info).
4. Ensure strong password and MFA stay enabled
   • Keep a strong, unique password that is not reused on other sites.
   • Keep Microsoft Authenticator (or another MFA method) enabled; do not remove MFA, as that would reduce security.

If this is a work or school account and the attempts continue, contact the organization’s IT/Help desk so they can review Microsoft Entra sign-in logs and, if needed, adjust aliases or apply additional protections.

References:

• Using Outlook mobile to sign in
• Common problems with two-step verification for a work or school account
• What happens if there's an unusual sign-in to your account
• Microsoft Authenticator FAQs
• Troubleshoot problems with Microsoft Authenticator
• Authentication did not complete
• How do I stop unknown persons trying to get into my Microsoft account. I have two factor authentication activated and keep getting requests to pick a number. - Microsoft Q&A
• Microsoft Authenticator keeps sending log in requests when I'm not trying to log in. - Microsoft Q&A
• Repeated Unwanted Microsoft Authenticator Login Prompts - Microsoft Q&A
• Someone is loggin in into my account from different location. - Microsoft Q&A
• People keep trying to hack me - Microsoft Q&A