HDFC Bank — Deducting my amount without my permission , as of now about 1000 they have deducted

I have used credit card for paying something.. and i didnt asked it to convert to emi but they have devided and into multiple months and adding one part of it to curent month for this process they are charging 99 for each transaction and 17 rupees as gst.. like this lot of times they deducted..
i didnt opt this.. and i paid my credit card bill before time.. without my permission why they are doing all this ... Please resolve this issue.