Amazon India — charged twice but amazon pay balance wallet loaded only once.

I was loading pay money in my amazon pay balance on 18th oct 2018 and i
Made 2 transactions to load 250 rs each time from net banking.
The first transaction failed during processing and the second transaction
Was successful but i was charged for the failed transaction also.

I checked with hdfc bank and raised a charge dispute. They confirmed that they have paid rs 250 twice to amazon and amazon have received the payment for both the transactions. Hdfc have also shared the transaction reference numbers for these hdfc-amazon transactions as follows:
Merchant ref no. : 3nnuvuhqmoffij7a27
Merchant ref no. : 3el1nuj7s9slcipt7x

Amazon is denying the same and it has been more than a month and i am still waiting for the resolution. This is not an acceptable behavior from a brand like amazon.