Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to Bitlocker key.
Step 1 In bios : boot options, change secure boot to disable . save and exit bios
Step 2 In bios : boot options, change secure boot to enabled , clear all secure boot keys, load hp factory default keys . save and exit .
Also Check using below url in case its backed up on a microsoft account.
https://account.microsoft.com/devices/recoverykey
Reference :
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