Hello, thank you for reaching out to Microsoft Q&A.
Could you please confirm whether you have two-factor authentication (2FA) enabled on your Microsoft account? If 2FA is turned on, you won’t be able to use the account recovery form to regain access to your account.
You’re likely being asked to complete the security form because Microsoft servers have detected unusual activity on your account. For security reasons, your account has been temporarily blocked. To prove that you are the legitimate account owner, you’ll need to submit the recovery form and fill in all the requested details as accurately as possible.
Microsoft takes account security very seriously, that's why Account Recovery is an automated process with no human influence. If you don't have the correct information, you may not be able to get through account verification using the Recovery Form.
Remember to use a familiar device from which you've frequently accessed your Microsoft account, as well as a familiar location. Microsoft will review your responses and respond within 24 hours. If you are verified, instructions on how to log back into your account will be sent to you, and if you are not verified, you will need to submit the Account Recovery form again. You can do this up to 2 times every 24 hours.
Alternatively, you can submit the account reinstatement form to the Microsoft account digital safety team to review the reasons why your account was disabled and help reinstate if possible.
https://www.microsoft.com/digitalsafety/account-reinstatement