HDFC Bank — refund not processed

On 20 Nov 2018 i have ordered Mi ear phones in amazon india[protected] and on the same day i cancelled that order and received a mail confirmation from amazon india on the same day with refund reference number[protected] and it is mentioned in the mail that refund will be credited to my account on 28 Nov 2018 but till not i haven't received any refund and am attaching the documents for your reference. Called hdfc customer care multiple times but they are telling amazon india have not initiated the refund and when i call amazon india they are telling that it is pending since hdfc people haven't processed further.