Coolwinks — not received cashback as promised

Website:

www.coolwinks.com

I ordered 2 sunglasses worth Rs. 1693. Order Id: CW[protected].
The order date was 26 May 2019. Order was delivered on 28th May. I ordered the sunglasses on step-out-sale offer, where promised to have cashback of 100% upto 2000. Link for sale description, also attached images : https://www.coolwinks.com/offers/step-out-sale/.

I had done payment through amazon pay wallet. After payment when I did not get the cashback, then I approached via mail to customer support, they replied that you will get cashback after 14 days are passed after delivery. Attached screenshot for the same. I have then waited for 14 days after delivery date of 28th May. When I did not received the cashback till 11, 12, 13 Jun, I again written the mail and then they replied they have technical issue in mail support call on support number, attached screenshot. On calling to given number, no one is picking the call. Most of the time it says lines are busy, when it automatic pickup, then also it keep saying all our customer support executives are busy at this time.

I need to have the cashback on my wallet as promised.