Canara Bank — refund not yet received in my bank account

I placed an order of ₹ 479 on amazon.in(COD), but since the product was defective I returned the item and asked for refund in my bank account which I haven't received yet . The bank claims that they haven't received any amount neither in my or their account though the refund was initiated on 7/03/19 . Refund reference number[protected]
My account number is[protected]
Refund was initiated on 3/07/19 and it should have been credited to my bank account by 14/03/19 and considering the delay it takes for the amount to reflect in my bank account, the amount should have been in my account by at most 21/03/19
Pls look into this and help me out .
Thank you