Can't install PBU because of firmware

Hi,

I am trying to install Proxmox Backup Server on my Server, but I keep getting this error message:


Things I have tried to solve this:

• Verified ISO is not corrupted
• Made sure that the USB is working (it can install Ubuntu without Problems)
• Connect the SSD to my PC and install PBU from there

All of this did not help, and I keep getting the same error message.

Can you help me with that?

Kind regards
Milou