Consumer Redressal

Hello Sir, I have been customer of ICICI from past 10+ Years, Recently ICICI had made me get ICICI Credit Card. My Billing Date for my Credit Card is 28th of every month. In the Month of August on 26/08/2022 I had made purchase of Product valued at 21,999 using ICICI credit card, which debited 21,999 from credit card. As I had cancelled the Product and Amazon has credited back the consumed amount of 21,999 to my credit card on 28/08/2022 which is same as my Billing Date. ICICI did not consider amazon credit and generated billing amount of 21,999. As I had the refund/Amazon credited back the amount I consumed from credit card limit I have not gone further to make any bill payment as it would simply create positive credit on the credit card. When I contacted customer care they were very rude, they did not bother to understand what has happened. I tried convince them saying bank did not considered the refund/amazon credit of 21,999 happened on 28/08/2022 and generated bill wrongly. Now ICICI had levied the late payment charges of 750rupees plus 135 GST on 18/08/2022. which they should not have done as there is already a credit of 21999 in CC account. I have asked for reversal of latepayemt charges as there is already credit of 21999 happened on billing day which would have negated billing amount and there was not a need to charge late payment charges. And ICICI still saying refund cannot be considered as credit in the credit card account. As It was mental torture to make them understand they should not have charged any late payment fee as there is already a credit of 21,999 happened on 28/08/2022 on the billing day., Still they did not listen and charged me late payment fees and asked to pay it. ICICI is fraud bank generated improper billing when there is credit already happened on the withdrawn amount. Later I had requested for closure of my credit card by clearing all the dues on 21/08/2022 by paying 19282(which included latepayment+gst amt). I had raised cancellation request of my credit card with the help of Customer care representative Vinay. Also Vinay had confirmed/gave affirmation that there are no other fees and credit card can now be cancelled. And he only raised the cancellation request on behalf of me saying it can be cancelled. Now ICICI credit card department is calling me again and harassing that I still have to pay some interest amount which will be generated in the next bill cycle and cannot cancel it. First of all billing of 21,999 is wrong as there is already credit of 21,999 happened on the billing day and ICICI did not considered credited amount from Amazon still generated false billing amount. Now after paying all the due which included late payment charges+gst which I was not supposed to pay and still paid from my pocket they are not closing my credit card. Now they are asking to pay additional interest amount of close to 3000/ which I am not supposed to pay. Please help over here . Credit Card dept at ICICI is uncooperative , unproffessionals, not understanding customers grievances. They are doing day light robbery with white shirt suit wearing ICICI Badge. It is total mental torture, I need legal help over here to face the ICICI.