Over due account

I had a loan with NSFAS, once I started working I requested for debit order deduction to pay my account. I have been paying for years now and am not seeing any difference in my account. the interest that is charged on a monthly basis just keeps increasing instead of decreasing my debt. <br> <br> NSFAS I would like to settle this debt. I need a full audit of the account because I have paid for 4 years and no difference