Amazon India — giving wrong reasons for non-refund

Website:

www.amazon.in

I ordered head strap for my action camera on 'amazon' for rs. 399 and the seller was 'mobile gear'. Within a week i received the wrong product. The item i received was mobile otg multicharger even though it was written outside package that it is head strap. So i demanded replacement from my app and within few days a person came to pickup that wrong product. Then again after 1-2 days, i received the same wrong product again. It was something mobile otg multicharger again. And again outside package it was written that it is a head strap.
So i quickly called the customer care and complained about the same. The person said that there is some trouble with the seller and adviced me to not to buy again from the same. They also told me to claim the refund from app. So i did the same. They told me that amount will be refunded once they receive my item to them and the process will take 3-4 days.
After 1-2 days again one person came and picked up the the wrong item and i was waiting for the refund.
These all incidencea happened during february end. Then i called amazon customer care again on 9 march 2018 for not receiving my refund. They checked in their records and said that i have returned them duplicate item and hence they can not refund me the money. I argued with them that there's something misunderstanding and they need to reverify again. But instead they blamed me and denied the refund.
I think the seller was the issue and it seems like some scam. The lady i talked to first also said the same.
Amazon, if you are reading this please verify with your records again. Otherwise i have to do a police complaint for this. The question is not about money but the blame they are putting on me.