Devo 12S filesystem crash afrer model edit

When I tried to edit the model in the Devo12S, the file system crashed when I tried a few times change and power off. When powering on, it just show the USB icon and when connect to the computer, it pops up to ask for formatting the flash disk.

I have tried and repeated for a few times, is there any know problem about the file system after 5.0.0 is released?