FINANCE CHARGE

Today i was going through my Credit card statement, I realised I was being charged R799 last month on the 7th of August and on the 7th of September i was charged R1186 as well and in July i was charged as well under description it says, Finance Charge which is very vague. The problem is i got a debit order with Nedbank and they always debit their money, so they took these Finance Charge without telling me and no one told me about this Finance charge before. i feel like this is not fair coz its not even included in your monthly statement , they just surprised you in every month. Someone sort this out and I want my money back otherwise i will have to paid up a credit card and close it :(