Mnt-root error during booting

Help
1

Hi,
I am new to NixOS. I downloaded NixOS 25.05 iso file. The checksum are matching. I flash my USB drive. I booted NixOS and got this error:
An error occurred in stage 1 of the boot process, which must mount the root filesystem on /mnt-root and then start stage 2.

mnt-root
mnt-root1024×576 49.2 KB

I pressed i and run:

fdisk -l
fdisk -l1024×576 62.6 KB

I flashed NixOS twice but error persist. What can I do?

2

What did you use to flash it?

3

I used Chromebook Recovery Utility which worked for debian and endeavouros. Should I used anything different?

4

I’ve never heard of that tool before so I can’t say for sure if it does what nixos needs it to do. For GUIs I always recommend either Balena Etcher or Rufus

5

Thank you it fix the issue.