Old Mutual is a ****

Old Mutual is ******** clients on loans.my husband took a loan from old mutual of R202 000 and he's been paying for 3 years now an installment of R5500 but the debt is not going anywhere and when he tried to enquire about this a guy got angry and dropped the call because he could not give answers.they say he's still left with 50 months and when we make calculations according to their 23.25% interest rate he should be owing less than R70000 but to our surprise and according to them he still owes R246 000 and mind you he has already paid R187 000 so it means their interest rate is 100% and more or they double the term on clients now when we calculate all the money he would have paid by the end of the term its almost R500 000.PLEASE HELP US! we dont know what to do now