AGX xvaier ubuntu rebuild issue

I have a AGX Xavier,it’s system is ubuntu 18,and I want to upgrade it to ubuntu 20.04.
So I use VM with ubuntu 20.04,followed with the official web to download SDKmanager.

I use type A-C to connect AGX ,and I’m sure it is in Recovery mode.
and next step I just let it start to download things.
Until now everything is normal.

form here start to be weird.
I notice that I can’t chose Automatic setup or Manual setup,there’s no options.
so I just enter the username and password,and start flash.

an hour later it jumped “taking longer than expected” message,I let it continue.
and it well always stuck at 38.27%.

I tried many times in these two days,and it always stuck at here.
somtimes I just quit and restart again.
everthing is fin in the beginning until it start flash.
it well jump error directly and say “the target is in a bad state”

What should I do T_T

VMs are not officially supported. During a flash the Jetson will disconnect and reconnect to the USB, which is the main point of failure for a VM. The VM must be told to always own that USB device, but often when the USB disconnects it will never see the reconnect. You’d have to verify with whoever supports the VM how to be certain that USB remains owned by the VM.

Also make sure you have enough disk space of type ext4.

OK!I got it!
THANKS