Amazon India — Defective product and No proper response from customer care

I ordered 4kg casa Copenhagen bean bag refill on Oct 23 but what they delivered was 700 gram bean bag refill.when I raised a complaint they assured on replacement the right product will be delivered.but what came gain was 2kg bean bag not 4kg.i initiated a return and I returned the product.but they created two returns and I can't see my return status.when I raised an escalation on Nov 27, they assured that the product reached fulfillment center on Nov 26 and by Dec 1 I will get my refund.when I didn't get and raised an escalation they are saying the product hasn't reached the warehouse and it will take 10 working days and by Dec 4 I will recieve my refund.i asked why they provided wrong info previously from escalation team.he was saying by Dec 4 I will get my refund and the product still hasn't reached the warehouse.for nearly 30 minutes of talking he was saying same thing again and again.when I called for another escalation .this time they were saying the product is returned to warehouse on Nov 30 and wait till Dec 5.each time I call they provide different info and give different assurance.when I first raised an escalation he assured so much by Dec 1 I will get my money.no proper response from customer care.they are holding my money and not giving it back.they didn't check product at all when they are delivering.on order slip the product weight was 4kg but what they actually weigh was 700 gram.no quality control.i am prime customer.order I'd:[protected]