Sales person harrasing mentally and not refunding

I had placed an order with Khushbu Jewellers for 1 payal worth Rs 1570 and 1 bracelet worth Rs 1000, through your sales person. I paid Rs 100 as advance, and I was told the balance of Rs 2470 was to be paid on delivery. However, the sales person booked the parcel with a COD amount of Rs 2670, which is incorrect. When I pointed out this mistake, I was told it was a mistake and that it would be cancelled, and the parcel was taken out for return. After that, I was given different and inconsistent responses each time I followed up, sometimes being told a voucher of Rs 1000 would be given, sometimes Rs 500, and sometimes that extra amount would be refunded through GPay. When I asked for the order to be cancelled, I was told the order would be cancelled but my advance payment of Rs 100 would not be refunded. This has been going on for about a month, with no resolution. I request that the order amount be corrected as originally agreed, or if that is not possible, my advance payment of Rs 100 should be refunded to me. I am raising this complaint not because of the amount involved, but because of the misleading and unfair treatment I have faced as a customer.