Max Fashion — non refund of my money for the partial delivery of online items from max fashion

Address:	560052
Website:	Maxfashion

My order no.[protected] from "http://www.maxfashion.in/" was delivered on 2nd aug 2018 at 10.58 am and the courier person collected complete order amount of rs.1638 as cash from me for two items but when i opened the packet there were only one item worth rs. 439/-and second item was missing. I immediately reported this issue on the same day to max customer care via mobile and email both. They told me that the product was not sent due to quality issue from their side and they cancelled the item order. But i had already paid to the courier person the full amount for which they told me that i will get the refund. Since then i am continuously doing follow up and every time they just reply that we have escalated your issue to concern department and wait for 24-48 hrs. And it's been more than 7days now, they have not refunded my money back and also haven’t responded to my complaint raised.
Please look into this issue as they have retained my money and not returning it back even after so many calls and emails.
I have also sent them the invoice copy attached in the packet for the proof.