If I am understanding this correctly you may have removed the USB drive from the console before the save was confirmed. This may lead to corruption of files and/or USB drives, but didn't directly reformat it. I would recommend deleting the file if you can (assuming the USB is readable at all) and attempting to place the file on the USB again via Copy in the File Manager in the shell.
You're right, I removed the USB drive from the console before the save was confirmed. I gave it 10 minutes before I gave up on it and pulled the USB. Sadly the first drive is now in RAW format and Windows cannot read it at all.
A drive showing RAW means some significant part of the actual filesystem is gone or corrupt.
That means the stick has died completely, or was disconnected while the filesystem was being updated so the file tables are missing or don't make sense.
If it's the latter, all may not be lost as Linux can sometimes read partially-corrupted drives.
Linux has some very clever tools that can make pretty good guesses about what used to be there.
There's a few USB-bootable Linux systems aimed at data recovery, I've not used any of them for years but your favourite search engine will lead to recommendations. Give that a go on a PC.
Unfortunately flash does wear out, and with USB sticks you'll usually lose everything on the stick when an 'important' page fails.
(I've even seen fakes that say they've got 32GB but are actually only 4GB. Everything saved after that first 4GB vanishes into the ether...)
As a wise woman told me more years ago than I care to remember: Cycle your disks!
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