USM8GU2 PEN DRIVE

Hello,
I HAVE SONY USM8GU2 PEN DRIVE BROUGHT FROM CHINA. BUT THE PROB IS FROM SOME DAYS THE DRIVE IS DETECTED BY PC, BUT NOT ABLE TO FORMAT OR USE ! I DON'T KNOW WHY THIS WAS HAPPENED ? SOMEBODY TELLS ME THAT UR PEN-DRIVE IS NOT GENIUN, THAT'S WHY IT WILL HAPPENS ! PLZ TELL ME HOW CAN KNOW THAT MY DRIVE IS FAKE ! MEANS WHR IS THE SERIAL NO. OF DRIVE & IF SOMEBODY HAVE THE SOLLUTION TO RECTIFY THIS PROB. THEN SEND ME ON MY ID ?

THANX