Myntra.com — Return declined because of quality check failure

I placed an exchange request for my Mango jeans on 8 December 2021 from Myntra. It arrived on (11th December). I decided to return it because it was a used pair of jeans. I requested for the return on 13th December. I clearly remember not misplacing any tags or anything that came with the product. The pick up was next day. I told courier guy that these are used jeans then he refused to take it and told me to file a complaint. I filed a complaint. After that a message was sent on my mobile saying my return request was "put on-hold" as it "failed to pass the quality check".
I called up the customer care and they informed me that the courier guy said that the product didn't pass quality check. Now why the hell would I do that? Remove the tags? What do you guys take a customer for? I have done shopping from other e-commerce sites and have never faced such a thing. It's you people who had sent a defective product. I should have opened the packet in front of the delivery guy, is it? If the product was undamaged when it left your warehouse, then why on earth am I not getting my money? I want my money back! Stop duping people like this. I want the refund.