Punjab National Bank [PNB] — Refund money not received in bank account

Address:

PNB Headquarters, Delhi

I have ordered one watch from Amazon on 14th Sep 2021 which has value of INR 9299 and completed the transaction through my PNB ATM Card. I returned the product and refund for the same has been initiated successfully from their side and it was supposed to get credited before 2nd October 2021. RRN for the same has been provided for the same from Amazon. I have visited PNB bank many times but always they said that we don't know anything. I need help in this as this is very big amount. Please find RRN for the same below.

RRN: SQB0VXTI0000KSNJ6HTB