Wrong product sent by PAYTM

The product I have ordered is 1 TB hard disk of Toshiba HDTB310AK3BA canvio basics and the paytm order number is 1153946144 but the product I have received is a different model i.e, Toshiba HDTB310AK3AA canvio basics and the invoice shows the same product which I have ordered i.e, Toshiba HDTB310AK3BA. when I have complained regarding this in [email protected] they said to send some images of the product,invoice and packaging. next day i sent all the images and they replied they provide a resolution for this issue in 48-72 hrs. after 24 hours they said to send some more images and next day i sent few more images. after 24 hours again they replied that they will update me in 48-72 hours. after 72 hours I told them that they are harassing me and i wil complaint in consumer forum regarding this but they just replied that we already escalated the complaint and we will get back to with an update in 48 hours. i dont know when this 48 hours will end. this is cheating as they are showing some product and sending other product. please look into this matter and solve it asap