Homeassistant Generic install fail : target is busy

Hello there,

i have here an mini pc and bootet ubuntu 24.04 from USB stick,

i try Generic x86-64 - Home Assistant

and when i want to restore i get the errormessge filesystem bussy. at the 2cend usb stick i have the downloadet image for HA restore.

what can i do now to set them up

at 6 times the same error, i cabt screw off the mini to get the HDD out to flash them extern

thank you for help