Repair pendrive yourself!!!

Open a Command Prompt With Administrator Rights And Enter The Following Sequence Of Commands:

-   diskpart
-   list disk
-   select disk {number}
-   clean
-   create partition primary
-   select partition 1
-   active
-   format fs=fat32 quick
-   assign
-   exit

In the "select disk" command, replace {number} with the drive number of your USB drive. Take care to choose the correct number since this procedure erases everything on the drive you select.