Hi, thank you for reaching out to the Microsoft Q&A forum. I’m happy to help.
The error message 'Please help us protect the security of your account' appears when the system detects unusual activity. Since you have tried different verification methods and the issue persists, your account may be blocked to protect your information.
Microsoft provides instructions on how to unblock it:
https://support.microsoft.com/office/unblock-my-outlook-com-account-f4ad2701-d166-4d8b-8a6a-9af2a1f8a4c4
If unsuccessful, you will need to fill out this account recovery form to regain access to your account: https://account.live.com/acsr
Microsoft takes account security seriously, so the recovery process is fully automated to prevent unauthorized access. Complete the form using a device and location you've used before, and make sure to provide an accessible email address.
Microsoft typically reviews recovery requests within 24 hours. If your request is successful, they’ll send instructions to help you recover your account.
Help with the Microsoft account recovery form: https://support.microsoft.com/account-billing/help-with-the-microsoft-account-recovery-form-b19c02d1-a782-dee6-93c3-dc8113b20c42
You can submit the form up to twice within a 24-hour period, so feel free to include any new details you remember each time until you recover your account.