Canara Bank — Refund Amount From Amazon Not Received After 20 Days

I have received a note from Amazon that my amount has been refunded to my account but I haven't received it as yet. They have provided a reference number as well however no one from your side has been able to resolve it.
The amount of this specific transaction was 1992 with reference number - RRN #30005111741174143424236. The order was placed on 23rd of June and the refund was said to have hit my account on the 30th. Nothing reflects in my bank statement and your customer support just keeps directing me from one place to the next.

This is one of many transactions that I haven't received my money in my account. I am very unhappy with your service, and feel terribly let down