Domino's Pizza — delayed order with missing item and yet to get promised refund

Address:

Pune, Maharashtra, 411057

I placed order on 27 july at 9.39pm, order number was 536. I got order by 11.20 pm and pepsi was missing from my order. Then delivery boy said that don't worry sir today its our issue and domino's is going to refund you your payment. Pepsi is not stock at store only so you will get refund.
I am waiting from then and i am yet to get any communication about refund.
Please help me with this and let me know where is my refund.