Amazon India — i'm complaining about computer spare

Address:	Erode, Tamil Nadu, 638051
Website:	www.amazon.in

Recently i bought portable hard drive in amazon. But it was not working. Only the light glows. Otherwise there's no detection in my computer. Even in my tv also. Also im checked in other computer systems. But its not working. So i requested for refund for that product. But amazon only gives replacement to me. But unfortunately replacement product also not working properly. So i contact customer care and requested for refund. For that request the courier executive came and picked up the product next day. But still now there's no refund issued for my account. Please do something.