Delta kitchen square - Item electric chimney for kitchen not delivered after taking booking amount

I booked an electric chimney for kitchen on ** Dec **** by paying Rs ****/-. Gulshan Singh was the representative who booked the item and take the money. After several phone calls which he is not attending now, he did not delivered the item. Either the phone is not reachable or switch off. Sometimes it rings but he doesn't attend the calls. I tried on each contact number which are mentioned on the bill, but no body is ready to attend the calls.