Repeated unauthorized sign-in attempts to my Microsoft account

Unrequested Microsoft Authenticator prompts usually mean either someone is trying to sign in as you, or your details were entered by mistake on another device/app.

Do the following immediately:

1. Deny every prompt you did not initiate
   When the “Are you trying to sign in?” or approval prompt appears and it is not from an action just taken, select Deny. This prevents the sign-in from succeeding.
2. Check for unusual or unauthorized activity
   1. Go to the Security basics page and sign in.
   2. Select Review activity to open the Recent activity page.
   3. Look for sign-ins or attempts you do not recognize.
      • If an event is in the Unusual activity section, expand it and select This wasn’t me.
      • If it is in Recent activity, expand it and select Secure your account.
3. Change the account password
   From the Security basics page, select Change password and set a strong, unique password that is not used on any other site.
4. Verify and clean up security info
   On the Security pages, review phone numbers, alternate emails, and sign-in methods. Remove anything not recognized so verification codes and alerts do not go to someone else.
5. Be aware of sign-in blocks and repeated attempts
   Microsoft may temporarily block sign-ins or verification if there is unusual activity or a high volume of requests, which can include repeated attempts by an attacker. If a “Try another verification method” or similar block appears:
   • Try another verification method already configured (for example, SMS instead of email).
   • Avoid repeated attempts; if blocked, wait at least 24 hours (up to a week in some cases) before trying again so the block can clear.
6. If you suspect ongoing compromise
   • Check the Recent activity page regularly to confirm no new unauthorized sign-ins.
   • If there is activity that is definitely not yours, mark it as such and follow the guided “secure your account” steps.
7. If you cannot sign in or the situation persists
   Use the sign-in troubleshooter via the sign-in helper link in the verification-code troubleshooting article to identify the issue and see available support options. If still having trouble after following these steps, use the official support channels described in the referenced articles to contact Support.

References:

• Using Outlook mobile to sign in
• What happens if there's an unusual sign-in to your account
• Troubleshoot Microsoft verification code issues
• Check the recent sign-in activity for your Microsoft account