Sending, receiving, and organizing email in Outlook.com
Hello, thank you for reaching out to Microsoft Q&A.
Could you please let me know if your account is locked, or if you recently updated your security information?
If you removed all of your previous security information and replaced it with something new, such as a recovery phone number, your account will be placed in a restricted state for 30 days.
Once the security information has been updated, you should be able to sign in by verifying your identity.
For reference: