Myntra.com — return refused to be picked up

I received men grey nike flex contact 2 running shoes on 29th june 2019.
Order no.:[protected]-6851201

After receiving and trying it on. The size was not fitting and we placed an request for return the next day (30th june)

The pickup delivery boy came on 2nd july 2019 and failed the product on the basis of quality check. He said it's been used (It had been worn just once inside the house to check the size) and said there's a stain on the sole (Only he could see it).
He said he won't pickup and talk to the customer care. I did that and they said to not worry and it'll get picked up. I received an email and stating the same. But again today i received an email that request for return has been put on hold. On calling up the customer care they said the product won't be picked up because it has a smell and failed quality exam (The pickup boy never mentioned any smell when he had come… i don't know when they added this to the list) they clearly stated the product can't be returned and now i'm stuck with a small size shoe worth so much money. I'm adding pictures of the shoe to prove it has not been used and there is no stain whatsoever... I also have the receipt….