Trying to regain access to admin account

Hey folks. I hope someone has run into this before. I need to somehow gain control of a Lenovo Thinkstation P360 but keep running into problems.

I am unable to boot into BIOS. I do not have the Admin password and have no way of getting it from the holder (they left the country). UEFI is not working so I cannot reset the computer. The original owner never made a recovery disc.

Maybe the BIOS is corrupted? My experience is with Win7 and Win10, but this machine is Win11 so maybe I am missing something.

Thanks everyone.