after an update the notebook with endless os stoped working, it is just a black screen with the same messaghe, no such device ostree, we read a theme here with a list of instructions, step first 1. Make sure you have a Live USB or DVD which contains sfdisk, lsblk, and dd. These are pretty standard Linux tools and are available by default on Endless Live USB. There are instructions on how to create a Live USB on https://support.endlessm.com/hc/en-us/articles/210654503.
2. Download the recovery script from https://raw.githubusercontent.com/endlessm/eos-meta/eos3.5/eos-tech-support/eos-fix-mbr-swap-removal.
3. Make sure the script is executable by running chmod 755 eos-fix-mbr-swap-removal .
4. Run the script as root with sudo ./eos-fix-mbr-swap-removal .
5. The script will point you to where it saved its logs. Please grab that log file and upload here so we can make sure everything went as planned.
6. Shutdown your computer safely, remove the Live USB / DVD, and turn it back on.
I think I managed to do the first step but then I have no idea what to do!