Amazon India — cash back not given after mobile recharge on december 20, 2019

Hi,

I recharged my mobile from amazon pay on december 20, 2019. There was offer of rs 45/- cash back. Normally cash back is credited to amazonpay account within few mins. But since i did not get cash back for more than 1 day, i contacted customer care over chat. I was told that cash back will be credited within 72 hours. But after 4 days i did not get cash back so i again contacted amazon customer care over chat and i was told that cash back will be credited in 7 working days. After i did get cash back for more than 7 days, i again contacted their customer care over chat. I was told that i will get cash back on or before january 14, 2020. Again contacted their customer care on january 21, 2020. This time i was told that cash back will be credited on january 23, 2020. I still have not got cash back and when i contacted yesterday, customer support of amazon india says i will not get cash back because there was technical problem and i was shown that offer because of technical problem at their end. If i would have known that they don't have cash back offer, i would have recharged from other site. Why should i suffer loss of 45/- because there was technical problem on their site.