First off, there is no such thing as a BIOS Admin password -- which is part of the problem.
There is a BIOS password, for which HP requires that you pay for the replacement of the system board -- as that includes the firmware where the BIOS password is stored, and a new board has new firmware.
There is the Windows Admin password, which HP will assist you in changing but you will have to provide proof of ownership of the PC. So, if this is the case, you should contact them back.
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