INTEREST RATE VERSES THE SISTEM

I AM TOTALLY AWARE OF THE INTEREST RATE BUT CAN MFC EXPLAIN TO ME WHY MY ONE CAR INSTALEMENT WENT UP WITH R665????? 28 MARCH 2023 R4469.95 .... 28 APRIL 2023 R5133.54 AND I AM SO SICK AND TIRED OF THE SAME OLD STORY ... THE SISTEM ..... NO NO NO .....IT IS THE PERSON BEHIND THE SISTEM SOUTH AFRICA!!!!!