What are the specific errors you're experiencing?
Have you tested the same USB drive in another computer and confirmed it's still working properly? The reason for asking this is because this rarely if ever has something to do with the OS. Plus you mention *"unable to copy audio or video files"... Can you copy other file types? Unlikely if you can't format it either. So, why mention those types specifically? This all reads as written by person without basic experienece with computers, sorry to say.
An update this year has rendered me unable to copy audio or video files unto my usb drive or even format said drive.Kindly assist.