Myntra.com — Return put on hold due to quality check

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Myntra

I have ordered biba sharara set from myntra, that was a prepaid order, but I get the same sharara set on offline store in less price, because that was a prepaid order my brother recieved that order because I was not at home, when I came back I simply put that order on return, without even opening the package, pickup is done and now my return is on hold due to quality check did't pass. How can quality check did't pass when even I didn't open the package, isn't it impossible? What's my mistake here, I think this is all done by pickup boy who was very rude, he must have gave wrong information in the company, I want my refund that was of cost 6000, what's my mistake here? What's the policy of quality checking in Myntra? How can quality check failed when I didn't even open the package?