Hi Gayatri Chede,
I understand this has been very difficult. From the description, this looks like a Microsoft account recovery issue together with a BitLocker recovery prompt, rather than a Classic Outlook issue.
Please note that this is a user-to-user forum, so contributors cannot access accounts, remove verification methods, or view BitLocker recovery keys.
If the PC is asking for a BitLocker recovery key, the first step is to look for the 48-digit key from another device. The published guidance says it may be stored in the Microsoft account, on a printout, on a USB drive, or in a work or school account if the device was ever connected to one. It also states that Microsoft Support cannot retrieve or recreate a missing BitLocker key. Find your BitLocker recovery key - Microsoft Support
If the problem is the Microsoft account verification phone is not available, use the Sign-in Helper first - Microsoft account sign-in helper - Microsoft Support. If two-step verification was enabled and there is no access to any other verification method, there is no manual bypass through support. If two-step verification was not enabled, the account recovery form is the available option. For detailed guidance on completing the form, please refer to: Help with the Microsoft account recovery form - Microsoft Support
To clarify the next step, could you confirm whether the device is currently showing a BitLocker recovery screen, and whether you can still sign in to the Microsoft account anywhere else?
For privacy, please do not post the full email address, phone number, or any BitLocker recovery key in the thread.
I hope this helps clarify the next steps.