Hardware errors are the most common reasons for data loss on USB drives. Due to excessive usage, frequent formatting, etc. hardware errors may occur. Sometimes these errors may be severe damages. Then it is difficult to recover data using a cheaper option like using data recovery software. In such cases it might be necessary to get the help of a professional data recovery service. If the damage is not that severe, you might be able to repair it using tools in the operating system itself. In most cases lost data on a jump drive can be recovered using Windows disk checking utility.
Simply right click on the icon of the jump drive and go to Properties, Tools tab, and then click Check Now in Error checking. Check both options (Automatically fix file system errors and scan for and attempt recovery of bad sectors) and click Start. The tool will try to repair your USB drive. If it managed to do that, your data will be restored.