Meesho — Regarding deduction of money thrice the product amount and denied refund from customer care

From meesho, a shopping app I had booked a order[protected]_1), where the payment option was only cash on delivery.
But before giving me the product to my address the delivery boy called and asked for amount and I paid too as
It was Cash on Delivery and I too have identified his indentification through his adhar and messho ID card.
He gave me the QR code and requested the payment of product which was of 480, but mistaken by me I paid 418,
to which he replied to pay the full cost 480 again and I have done so as he said the previous 418 will be refundable.
He still then asked to pay full sort of 898 for previous transaction linkage so that they can deduct the required product
amount i.e 480 and give me the remaining amount as refund.Till then I had paid 1796 for product cost of 480 i.e. almost thrice
the price of the product.But it was very very surprising when he again asked me to pay 2500
as GST cost of product.When I called him again clarifying the message that I recieved to pay 2500 from meesho he
then too asked me to pay 11000 for it.Why should a consumer should pay such a high amount for the product which didnt
cost half of it? I complained same thing to customer care of meesho but they too denied to refund the money
which was already credited for unreceived product. Filling complain to atleast receive my money which were already deducted on the name and trust of company!!