When flash trueNAS.iso to USB drive, err show as connection process failed

Hi pls help:

My PC is ubuntu 24.04, I want to make a USB drive for trueNAS system.

balenaEtcher for ubuntu has been downloaded.
The iso file is downloaded from official website.

But, when I click “balena-etcher”, choose the iso file, choose the USB target and flash, it shows error as:

I’m very sure the iso file is good, and the USB drive is OK (I try to changed 2 USB drive, also try format the USB drive), pls help on this error, many thanks~