If BitLocker has problems unlocking the drive, you may need a recovery key to continue. To help retrieve previously stored BitLocker recovery keys, this article describes the different storage options for finding your BitLocker recovery key.
If your PC is connected to a domain (usually a work or school computer), you can ask a system administrator for your recovery key. If your PC is non-domain-joined PCs, and you did not backup the BitLocker recovery key initially, you could also retrieve the key through the clouds, as long as your PC is signed in with Microsoft account.
There are several options in Windows 10 that may save the BitLocker recovery key:
To retrieve the recovery key that was saved to a Microsoft account, go to visit this site: https://account.microsoft.com/devices/recoverykey, log in with your Microsoft account, then you will see that recovery key.
To find the key that may be saved to a USB flash drive, plug the USB flash drive into the locked PC and follow the instructions. If you save the key as a text file on the flash drive, use a different computer to read the text file.
Retrieve keys that may be saved to your computer. If you have not removed or deleted it, you can look for BitLocker Recovery Key.TXT file on your computer.
If you want to find a location where you can print or save your BitLocker key, you can find it in a paper document. Additionally, the BitLocker recovery key may have been printed to Microsoft Print to PDF and then searched for PDF files on the PC.