Myntra.com — Return put on hold (they say it's used product)

Address:

3rd Floor, AKR Tech Park, 7th Mile, Krishna Reddy Industrial Area, Kudlu Gate, Bangalore – 560068, Karnataka, India.

I ordered a track pant from myntra (order id is 115440632617963384901) on 13th of october and received the product on evening of 19 october. the product didn't exactly looked what i expected it to be, it was a bit dull in colour and a bit too loose so i requested to return the product the very next day. they picked up the product on 21 october and the delivery guy told me everything is fine and now they are saying that the product didn't pass the quality check because it has been used. i mean how would I even use it if it didn't even fit me.
now i don't know what to do .