Amazon India — refund is not received

I have purchased an item and it was defective as I requested for refund amazon has accepted it.
As per the amazon representative the refund has been initiated on 26 June to which I had called 6 times.
1stly they asked me to delete the bank account details and re-enter it. I did it while they where on line.
Now when ever I call they ask me to do the same every time.