[Resolved]  Punjab National Bank [PNB] — refund not credited into account after estimated limit

I purchased san disk ultra dual 64gb usb 3.0 otg pen drive ₹1785 from amazon on 27/01/2018 and done full payment by internet banking but order was cancelled on 27/01/2018 and now amazon is saying that refund has been send to bank. So contact customer service and file charge dispute they had given me a no. Refund reference number# [protected]. But customer service is saying they can file nothing like charge dispute and can only check if money came to your account or not.
Same behaviour by branch also.
Don't know what to do
I attached the email from amazon.in