Myntra - refund not credited

This is with reference to order id # ******* **************.I had placed an order request for IEEE and had placed the return request for the same on **th March.The product got picked i ** March and the pickup executive said that i would get the pickup confirmation on app.I did got the confirmation o the app but havent received the refund yet.Despite of calling the myntra customer care ten times I havent received the refund.Now they are denying the refund on the grounds that the product has not reached their desk.They asking me to share the receipt that the product was picked up.I have clearly stated that no receipt was shared at the time of pickup amd Pickup confirmatio was received on my app.Earlier they had said that the product is undergoing quality check now they are denying that the product has not been received. Plz look into the matter