Myntra.com — no product - no refund

Address: 400053

I had returned a product called "arise shorts".
I returned for the reason because i do not use that material as it is woollen, and the website mentioned cotton.
Their pick up person did not update their system for the return and someone else again came for the pick up the next day.
Their executive said quality check has failed and they will return the product and i will have to re-return the product.
Later they said i sent a wrong product, whereas that was the only product from that company i had ordered.
Then again they said qc failed.
Their senior executives are also giving me different answers.
It has been around 3 weeks they are not responding and only asking for 24 and 48 hours every time their previous deadline is reached. No one is ready to give the information of their grievance department as well.