Punjab National Bank [PNB] — Refund not reflecting in bank account which was processed by Amazon in MasterCard Debit card

Address:

PNB Mathura

On 27th July, Amazon processed Refund of Rs 370 for an order to my PNB Debit card ****9495 and on 30 July, they again processed another refund of Rs 409 for another order to same debit card. Even after waiting for more than 7 days, I didn't received amount in my bank. I had complaint it to my bank customer care but they said we can't do anything, kindly go to bank. When I reached bank and told them about my complaint they said they don't do anything for online transaction. Amazon has provided me refund Reference number for both refund Transaction but bank is denying for this. I knew this is fault of PNB bank.
Both Refund Reference No( RRN) are attached below-

RRN 1 for Rs 370: 85215220210029286818423

RRN 2 for Rs 409:
85215220213030430832523

The following are my bank details:
Bank Account No : *****044002
Bank Code : 491700