flash drives are easily damaged, especially when pulled from port while it is still working. You can try running chkdsk and have it fix any errors.
the easiest way it to right click the drive in my computer - click on properties - tool tab - checkdsk.
It fails to format unless I use the quick format option. And when I tried to move a lot of files to it, it disconnected and the pc said the files were no longer located in that location and asks me to skip it or try again. and it beeps every time it disconnects. its not a new usb drive but i dont know why it would have been damaged.

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