Canara Bank — regarding not refunding of the amount issued from amazon and its been almost 4 months and proper response even after contacting several times

Dear sir

My registered mobile number [protected]

I purchased a product on amazon on 27th september 2019 using my canara bank credit card number [protected].. After that i returned the item and i asked them for refund. As per their confirmation refund was initiated on 30 th september 2019 maximum time frame was 5 days. Still it was not reflected in my account. They had provided the refund reference number as 0r9x0lo90000k0ocng1g and i had contacted your customer service number several times and there is no proper response and u people saying reference number is incorrect. But i verified it from amazon and its correct.. Hence i am sending a mail. Please check and confirm the status if your response was worst in mail too i'm going to file in banking ombudsman.