Punjab National Bank [PNB] — Refund not reflected to the account yet

On 23th of February, 2021, I made a transaction with Amazon of Rs 17080.00 for ordering a processor But returned it due to fault in it and opt for refund and Amazon has initiated the return and refund on dated 23 Feb 2021 but it has been over the 5 days I yet to receive the refund in my PNB account.
Whereas in the app of Amazon it is saying that payment transferred to original payment method. Customer service of Amazon is saying that we have refunded and generated RRN no., it's your bank problem and customer service of PNB is saying amount not credited and we cannot check through RRN no. Please do the needful and resolve my problem . This is a miserable condition I am facing.