Indian Bank — refund amount not credited to the account

Hi, i have been issued a refund through amazon on 28th dec 2018 at 11.26 am which should be credited to my account on 30th dec as per amazon. Amazon said the reference number which is 457440 has been generated in relation to the same and is only generated when bank accepts the payments. Even after repeated followups, bank said there is nothing they can do there is no entry is passbook and amazon said to they have already issued the refund. I'm based outside of india and it is very difficult for me coordinate with bank branch. I had my dad went their twice with no fruitful result. They are very uncooperative even amazon has stopped replying to my emails. Not sure where else i should reach out. The indian bank branch is tilak nagar, new delhi. I can provide further details, if required.