10 Pro w. Bitlocker - have recovery key but can't get the drive unlocked

[croge2k]

Surface PRO 4
Win 10
Bitlocker with TPM
recovery key backed up (and I have a printed copy in front of me)
Automatically boots in to Bitlocker recovery.
Message says : You need to enter your recovery key because Secure Boot has been disabled. Either Secure Boot must be re-enabled, or Bitlocker m ust be suspended for Windows to start normally.
KEY ID as noted on this screen is 8f3CF0BB
KEY ID on my printout also says 8F3CF0BB
48 digit recovery key won't unlock
error message says: Failed to unlock with this recovery key

tried to boot to win 10 boot USB that was created with media creation tool many months ago and run a command prompt and try the DOS commands to unlock
manage-bde -unlock c: -rp xxxxxx-xxxxxx-xxxxxx-xxxxxx-xxxxxx-xxxxxx-xxxxxx-xxxxxx
get a similar message.
tried to boot to a winPE environment but for some reason those don't work - I've tried burning 5 different ISOs FAT32, NTFS, UEFI, UEFI/BIOS nothing works.
wanted to at least try a windows environment and try clicking on the drive letter in explorer and get prompted to unlock - and then attempt to enter said recovery key to see what it does - but can't get a PE ISO to work -
so i'm kinda out of ideas - and I can't even reset it because when I go to recovery options it says that it can't continue because the drive is locked - although I'd rather not blow it away because the user has outlook PST files that we need to recovery!

any suggestions?

 

[Barty1884]

I'm really not sure...... but judging by the actual message you received "because secure boot has been disabled"....

Does everything work as intended if you re-enable secure boot?

 

[vrumor]

Contact Bitlocker. No one here can help you.