Hi Walt,
Thanks for reaching out Microsoft community. It sounds like your Surface Pro X unexpectedly showed the BitLocker recovery screen, and the usual diagnostic steps haven’t resolved the issue.
To help further, could you confirm if any recent changes were made—like a firmware or UEFI update, or boot configuration adjustments? Also, is this a personal device or managed by an organization?
If it's personal, you can retrieve your BitLocker recovery key by visiting https://aka.ms/myrecoverykey and signing in with your Microsoft account. If it's a work device, please contact your IT department for the key.
For more details, you can also check this guide: Find your BitLocker recovery key: https://support.microsoft.com/en-us/windows/find-your-bitlocker-recovery-key-6b71ad27-0b89-ea08-f143-056f5ab347d6
Let me know how it goes!
Warm Regards,
Edward Schlobohm