You need to unlock encrypted external drive then access to it, need password or recovery key.
In my opinion, turn On Auto-unlock for your external drive is feasible.
Detailed steps here:
https://www.tenforums.com/tutorials/37662-turn-off-auto-unlock-bitlocker-drive-windows-10-a.html
Please note: Information posted in the given link is hosted by a third party. Microsoft does not guarantee the accuracy and effectiveness of information.
Regards
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