Indian Bank — charge dispute form from amazon india

As i have ordered an item from amazon and successfully delivered to me but i cancelled it due to some issues in the product and requested for a refund amount of Rs.2120 on August 17, 2019 they was initiated the amount from their end on same day 17/08/2019 and the reference no is:285560 but amount has not been credited to my account till date and continuously i am contacting customer care for this but not getting a reply for this. As per them contact branch for complain, they put an ip from there side whenever branch contact to the department they said today will credit it but still in pending no action is been taken. As per amazon they instructed to file a charge dispute. Please look into the matter at the earliest. Please look into this matter as its very serious
It's been 7 months till date i didn't received the refund of the order..
My account no: [protected]
ifsc: IDIB000S107

please help me with this.