Hello there,
Have you made any recent updates that you are aware of on this device? If so try uninstalling them and check as updates as history of breaking this feature.
You can also enable or disable BitLocker auto-unlock from the Command Prompt. And while knowing how to do this isn't essential, learning how to input commands in Command Prompt is a useful skill.
Make sure that the drive is plugged in and unlocked. You can't enable auto-unlock on a locked drive for security reasons.
Type cmd into Windows Search and run Command Prompt as an administrator. You need to have administrator (elevated) privileges to make changes to BitLocker using this method.
To enable auto-unlock, type: manage-bde -autounlock -enable H:. Replace H with the letter assigned to your removable or fixed data drive.
Hope this resolves your Query !!
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