HDFC Credit cards - EMI not coverted

Credit Card Number:xxx xxx xxx ****
I booked an airticket on **th October through paytm for an amount if **** rupees for * months EMI with **** approx as EMI amount . I got the ticket and generated an invoice with EMI transaction no/banking ref no.***************. But in the statement there no conversion of EMI as my bill generates on **th every month. Its been ** days there is EMI procees in my statement. Full amount is being billed instead of EMI amount. I wrote a email to HDFC on ** th october stating this problem ,since they are postponing , saying they will revert back on **th oct, then on **st oct, then on *th Nov and finally on **th November. My due date is on *th November. on * Novermber they told on telphonic call they will resolve before the due date and you don't have to pay the entire amount, as we will take complaint if no action is taken on *th November. Now they are not responding, so I had to convert under smart EMI scheme, to avoid late payment and further interest on my due, which cost me ***, instead of *** as interest is for * months as they don't do for * months. I need a solution