Thosiba external hard disk
Not getting warranty

I have purcahased an external hard disk dtd 7/06 (sl no:41TDCDLAT MC3 ECA) and is not working properaly after one year .i approch the thosiba service centre calicut but they took the serial no and said that this product is not in their list .this product is online purchased through e-bay. the product has three year warranty. what i do.