Indian Bank — indian bank refund amount from order cancelled with amazon but not credited

I have ordered a mobile of cost Rs 12999 with Amazon on 06.01.2019 and cancelled it after few minutes . I had got mail from amazon for refund with ref no[protected] . They had said that the amt will be refunded within 3 to 5 business days . But I did not get my refund till now 03.02.2019. I also contacted to my Indian bank's customer care so that they could locate the refund with the reference no. But customer care executive failed in doing that and she said to me to fill the charge dispute form. And i searched it online but i didn't get the charge dispute form. So kindly look into the matter and process my refund soon. My order no.[protected]