ICICI Bank — Credit card charges refund

Address:

MUMBAI

As you know I am paying all my dues on time but in April - 2022 statement there is an addition of interest charges of Rs. 5060.85 & CGST - Rs. 455.48 & SGST - Rs. 455.48 which has been added by mistake and you have to refund back and spoke about the same to your customer representative and told that refund will be done.
I have been taking follow up since last one year but no response from your side.
Sir, its been 1 year and till now there is no resolution from your side and no support. I tried calling your representative and always they have told me that its processing and it will take 2-3 days but still haven't received any refund.
Everytime different person is picking up the phone and i have to narrate the story.
It's my genuine request to do so and clear all the interest charges and GST Levied on them.
How much time it will take to resolve this.