LOAN INTEREST IS ****ING ME AFTER GARNISHED

I HAVE BEEN GARNISHED FOR A LOAN THAT I DID NOT PAY I AGREE BUT I COULD NOT AFFORD IT AT THAT TIME DUE TO MY CONTRACT HAS EXPIRED AT MY PREVIOUS JOB . NOW IM PAYING EVERY MONTH BUT CAPITEC BACK DOES NOT WANT TO WITHDRAW THE CASE AT JDT FINANCIAL SERVICES THE COLLECTORS. JDT FINANCIAL SERVICES IS ****ING ME WITH INTEREST ALREADY PAID R35100.00 JUST ON INTEREST. I WANT TO MAKE ARRANGEMENT WITH BANK IT SELF THAT I CAN CANCEL INTEREST AND SETTLE ACCOUNT AS SOON AS POSSIBLE. CAN NOT MAKE ANY DEBTS DUE TO THIS LOAN THATS KEEPING ME BACK