HDFC Bank — cashback not received: iphone xr purchase

Dear sir,

I bought an iphone xr from poorvika mobiles, chrompet, chennai on feb 8th through my hdfc bank debit card emi option which promised to offer rs. 5000/- cashback within 120 days from the date of purchase. It has been 142 days and i still have not received the cash back from hdfc bank.