@Redistro，Thanks for posting in Q&A. From your description, it seems the device turned on BitLocker when sign in your work account. Please check if other BitLocker policy has assigned to the user or device group. If yes, unassign the previous policy.
Then try to decrypt BitLocker Drive via one of the methods in the following link:
Note: Non-Microsoft link, just for the reference.
After that, apply the new BitLocker policy to the user or device group to make it work.
Hope the above information can help.
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