Clip+ Cannot fully flash, same FAT is corrupted error

Hey guys, 

I’ve tried looking everywhere, though nothing helps. After using the sansa clip+ as a USB for bootable DVD it does not boot up (used it as bootable device multiple times before). Tried to format it in all possible ways, it just doesn’t fully flash. Cannot install neither the original firmware, not the Rockbox. Whatever I try doing, it still says “FAT ir corrupted. Please connect device to PC and”. Anyone here could suggest an option? You’re my last hope