Amazon India — Amount refund for an online order cancellation

Address:

West Godavari, Andhra Pradesh, 534202

I had cancelled an online order with Amazon India bearing
Order #[protected] placed on 4th March 2017 for an amount of Rs.319/-. Refund was not credited to my bank account till today with Debit Card of SBI last four Digits 1716. Amazon gave me a refund reference number for this transaction as 617301. I contacted Amazon customer service several times. they say that they processed the refund and SBI gave this refund reference number so there is nothing pending with Amazon. They also suggested to contact SBI Customer Support quoting this reference number and ask them to clear this issue. I had also done this several times. SBI Customer care Executive says they have nothing to do with this reference number and contact the Amazon Customer Suppot, I contacted Amazon and explained the status this issue. They replied to contact my SBI home branch and file a charge Dispute to resolve this issue. My SBI home branch officials say that they have no idea what is a charge Dispute and they also tell that they not even heard about that. So my issue is travelling in between SBI and Amazon. Can you help me in this regard