[Resolved]  Amazon India — they are not giving my cash back as per their sale

I had brought moto g4 play at the cost 7999/- on dated 14th may from amazon.in and there was offer that if you are purchasing it by credit card then you will get 15% cashback that will be credited up to 11th august 2017 and i brought that mobile from credit card as as per there sale there was 15% cashback which will be credited by 11th of august 2017 but the thing is i have completed to the site so many time but they are not providing cashback return to my account and now they have cross the limit even they are not receiving phone call from my side as the recording said we are unable to fetch your product so the my question is when will be my cashback return to my account because it was a 50 days time now the date is 20th september 2017 i have called them so many time but they are not giving my cash back to my account.

Please help me getting a cashback return to my account.