https://www.amazon.in/b/ref=dash_apay_hfc_bills...

Collect Amazon Pay offer – Recharge & Win Rs.10 to Rs.300 on Prepaid Recharges would expire on 31-Mar-2019.

Next steps:
Recharge your prepaid mobile using any payment method on Amazon.
Cashback will be credited as Amazon Pay balance within 3 working days of recharge.
This offer is valid once per user for the duration of the offer and cannot be combined with any other offer.
Read detailed Terms and Conditions here