Amazon India — Amount has still not credited my account after getting refund

Hello

This is Tejas TS and my account number is ([protected]), I had purchased a product on Amazon on 14th November using my card worth 278, and I got a refund from them on 20th, and it has still not reflected in my account, when I contacted Amazon they said me to call pnb customer service, when I called them, they said me to mail the issue, but i did did not get any reply from bank after 2-3 days of sending the mail.
Amazon has sent me a mail giving me the reference number #5134040326028921735538 of the refund, can you check and let me know, where has the money gone.
I have attached my bank statement and Amazon reference number mail, so that you can have a check.