|Could be the flash drive itself is faulty. Copy its contents somewhere safe then try formatting the flash drive - it might help. In your computer you right click on the flash drive then go to Properties. Windows key + E key should find your drives. Even if it fixes it I wouldn't trust the flash drive again - they have a limited life.|
Otherwise see if there are any USB errors showing in Device Manager (right click Windows icon bottom left of taskbar).
Always pop back and let us know the outcome - thanks