Hello Nirmal Neupane,
thank you for posting on the Microsoft Community Forums.
Formatting your C drive can lead to issues if it contained the operating system and configurations related to BitLocker. Unfortunately, there is no way to bypass BitLocker without the recovery key unless a full system reset, which would result in data loss. To retrieve your recovery key, please follow the steps in Find your BitLocker recovery key - Microsoft Support.
Since you mentioned that you checked your Microsoft account but didn’t find the correct recovery key, please ensure you are checking the correct account. If you have multiple accounts, log in to them one by one to see if the correct key persists.
Important: Microsoft Support is unable to provide, or recreate, a lost BitLocker recovery key.
Best regards,
Lei