Myntra.com — Mental harassment

I ordered a shoe and got a different product and it has been approximately 20 days now, I am daily calling them and they are just saying that your complaint will be resolved within 48 hrs, but their 48hrs never comes
The delivery boy never calls me and cancel the pick on his own everyday, The first pick up I ordered, the delivery boy told to take the approval and then I took the approval from the myntra executives and then the delivery boy told on call that nothing can be done with an approval we can’t pick up your order.

Each and every time I am calling the executives and they are just keep on delaying the process they just say I have addressed your complaint and then they never update, Now I am feeling pathetic and mentally harassed

I want my compensation and the pick to be done asap without any questions asked.