A phone number has been requested. This was not me.

If an unrequested verification code or phone-related prompt appeared, do not approve it and do not respond to codes that were not requested. Without the code, the account remains protected.

For a Microsoft account, unrequested verification codes can mean:

1. Someone is trying to access the account.
2. Someone entered the wrong phone or email by mistake.
3. A previously requested code was delayed.

Since Outlook is still accessible on the phone, the safest next steps are:

1. Keep denying or ignoring any sign-in or verification prompts that were not initiated.
2. Check that the sign-in name is correct if prompted, including the full Outlook/Hotmail/Live domain.
3. If the security info shown during sign-in is unfamiliar, use the account recovery path.
4. If access to the account is lost, select I don't have any of these during sign-in and follow the prompts to update security information.
5. Use Microsoft’s sign-in helper if sign-in problems continue: Start sign-in helper.

If the issue is specifically in classic Outlook for Windows and Outlook prompts to confirm a phone number with the error "The Microsoft account doesn't exist. Enter a different account or get a new one.", that was a known issue that was fixed in Outlook Version 1905 Build 16.0.11629.20246. Install updates in Outlook through File > Office Account > Update Options > Update Now.

If that Outlook prompt still appears after updating, there is a registry-based workaround for non-Windows Store Office installs. This is a higher-risk step because incorrect registry changes can affect Outlook profile sign-in behavior:

1. Close Outlook.
2. Open Run, type regedit, and open Registry Editor.
3. Go to **HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities**.
4. Find the Outlook.com identity key such as ******@hotmail.com_SSPI.
5. Delete that account’s identity registry key.
6. Then delete the Credential Manager entry for the Outlook.com account.

This workaround does not apply to the Windows Store version of Office.

If sign-in cannot be restored through self-help, use Microsoft support options for Outlook.com or Microsoft account help.

References:

• Troubleshoot Microsoft verification code issues
• Contact Microsoft customer support
• Outlook prompts for phone number for Outlook.com accounts