Hi! I'm Richard, an Independent Advisor.I'm here and ready to help you today!
Thanks for your message. It looks like your Surface Pro 9 isn’t detecting the TPM chip, which is why it keeps asking for the BitLocker key. Since the device shows TPM not found and the device manager shows an error, this might be a hardware issue.
What you can try.
Update your BIOS/UEFI firmware.
Reset BIOS settings to default.
Check if the TPM can be enabled in BIOS if the option appears after update.
If these steps don’t work and the TPM still isn’t detected, it’s likely a hardware problem. In that case, I recommend contacting Microsoft Support or an authorized repair center for help. They can give you a quote for fixing or replacing the hardware.
Let me know if you need help finding other assistance.
Kindest Regards,
Richard R.