I have had a similar thing happen with a decent 128GB USB flash drive which my media player has twice corrupted the firmware/controller. The first time I managed to fix it but the 2nd time I did not. I think I might of used the wrong tool to fix it and made it not usable in the process.
There are a couple of Russian sites which deal with flash drives and contains lots of tools to fix flash drives and read in depth information on them such as the controller used and the correct size. I remember at least one of the information programs being Chinese.
I purchased a 2TB flash drive on eBay which was fake and the seller refunded me. Using a tool from the Russian site I managed to correct the drive size which was originally a 16GB drive with half being faulty and therefore very cheap which is why they used them to alter the drive size to show as 2TB. It worked as a 8GB drive which is how I use it so it was okay for free even if nothing special.
A few of the program names are: ChipEasy, ChipGenius & Flash Drive Information Extractor. You start with those to find out the details about the drive and then you can find appropriate programs to correct the faults. Best of luck.
https://flashboot.ru/files/
https://www.usbdev.ru/
