Credit card account

I am a life long customer of Absa. My outstanding balance on my credit card account is ?R60 000.00. I do pay my account of R2 000.00 strictly every month. What bothers me is that after all the month's being paying NOTHING comes off the amount even though I don't use the credit card. The call centre agent phoned me this morning regarding the account. I asked the guy about this and he rep**** that an amount of ?R800.00/m is going for interest every month. When I asked him what's happening with the rest of the money (R1 200.00) he rep**** \because you are paying late it is going for interest". This is totally unacceptable. I hardly gets any pension and my children from Australia is supporting me to survive but the money doesn't come in every month at the same date. That is why the amount is not payable every month at the same date. My question is why is my outstanding balance on my credit card"