Grofers — missing item

Address:

Gurgaon, Haryana

I'm ordering from grofer for a year and there was been a 1-2 problem which they solved very quickly.
This 25th oct'19 i have scheduled a order but that order was late and i had to go somewhere so i told my mom to receive the order.
My mom received the order and paid the amount rs 1630 (Full payment).
On 26th oct, i came back home and asked mom if she received all the items she said that"did i didn't ordered the butter (Rs220)?" then i saw the bill their was no mention of butter but online it was showing.
I filled the complain against a missing item but they told me that there was no missing item and that they will not refund the money because order was cod. On 28th oct, they told that a delivery executive will come to my house in b/w 10:00-1:00 but no one came i waited whole day.
From 26th oct till now 29th oct there is same reply.
I have sended all the screenshot and photos to grofer. This time i'm so disappointed.
I just want my money back.