2 long 2 short beeps. HP Probook G4

Hi,

as it is in the title, I'm getting the 2 long 2 short beeps error when trying to boot up. And by trying to find info about it, it's suggested it's probably a corrupted BIOS. Using the key combi Win + B, beeping stops and fans are running and that's it, no screen comes up.

I've still tried to make a bootable USB as seen online to flash BIOS, but I'm doing it on a ASUS laptop and when trying to follow the wizard, I'm getting: "The file is missing or corrupted error" and the option to put it on the USB drive is greyed out.

I'm getting desperate here, any advice?