Amazon India — Issue with return

I raised request on 9-Mar to return product "On Whey protein" and its return window showing is 12-Mar.
I was committed to pickup the item on 10-Mar, I waited whole day and now I was told by customer executive that I was not available at home (which is totally false). I tried reaching the pickup person on Amazon generic number (received with PIN) about 10 times but he disconnected my number.
One of the executive told me pickup will happen on 11-Mar, but still there is no update on the website.
I have seen the negative feedbacks for Amazon regarding return.
My order number is - 9958 (at the last)
Request to get it resolved and refund the amount ASAP, the amount is 5003.