PayTM - Refund not initiated

I had booked a Macbook Pro Online which was supposed to be a gift for someone. The delivery date was shown as *th May. The customer care hardly picks the call. On calling repeatively they assured me it will be delivered by *th May. However it was not even shipped by *th May. After all effort I had to cancel the product so that I can purchase from somewhere else. However on calling customer care they said as of now they cant refund my money, it may take more than ** days. I wanted an explanation from them when my item is not even shipped, why they are not refunding my amount., to which they had no answer. Till date my refund is not initiated. I keep calling customer care but its all in vain, as they are not receiving calls.