Amazon India — Cashback has been declined

Order number:[protected] dated Nov 15 2020

I have placed above mentioned order availing cashback offer. The cashback offer said that if i place an order for Rs. 900 or more then i will receive a cashback of Rs. 300.
After placing the order- i called the customer care and specifically asked if there are any terms & conditions for that offer and was told that my order was eligible for it and i should get the cashback in 2-3 days.
But later i realized that cashback has not been issued to me as per the offer. When i complained to Amazon on 20th November then again i was told that they will escalate this issue and ensure cashback is issued within next 7 days. Unfortunately that didn't happen.