Get Flat Rs. 100 Cashback on Adding Rs. 500 or More on Amazon using unique code from Zeta App. Add minimum Rs.500 Amazon Pay balance and get flat Rs.100 cashback. The unique coupon code available on your Zeta app, needs to be applied on payment selection page on Amazon, while loading your Amazon Pay balance to get the cashback (On Add Money Page select ‘Other Payment Methods and Promo Codes’ option and click continue. On the next page click on the ‘Add Gift Card or Promo Code’ at the bottom to enter your coupon code). The cashback amount is limited to maximum amount of Rs.100 per customer. The customer will receive the cashback amount in the form of Amazon Pay balance, which will be credited to their balance within 3 days of the transaction.