Indian Bank — refund credited from sellers side but not reflected in my bank account

Address:

444601

I had purchased a mobile phone from flipkart on 23/12/2019, paid for it through indian bank debit card and cancelled the order on the same day. The maximum date for the refund to be processed in the account was 30/12/2019. I contacted the bank and gave them the refund reference number but they are not providing me the required information.
I asked them for charge back form, but they are denying it by saying that there is no such form.
What do i do please help.