Not returning my payment for air conditioner and not delivering the product

I had paid for an Akai air conditioner unit to be delivered to me by Diler Singh. The payment was taken in 5 to 6 separate installments, with a gap between each payment, and one of these payments was Rs. 20,000 made in cash. And other payment in upi payment Despite receiving the full payment, the AC unit was never delivered to me. When I asked for either delivery of the unit or a refund, he kept giving me excuses and postponing the matter, saying he would return my payment later, but he has not refunded any amount till now. I request that my full payment be refunded immediately, since neither the product has been delivered nor my money returned despite repeated assurances.