Hello, thank you for reaching out to Microsoft Q&A.
May I know if you are being prompted to enter your Windows Hello security PIN when signing in with your Outlook account? (i.e. the Windows Hello sign in PIN you use to log in to your computer)
Could you please provide us with a screenshot of the security screen for reference? (Make sure to hide or blur any personal information before uploading the picture here.)
we will be waiting for your reply.