student loan amount not reducing after years of surety paying interest and fees

I'm typing this very angry and frustrated, i took a student loan with standard Bank for my first and second year studies in 2017, and 2018. My gaurdian was surety for the loan and was getting debited R2600 every month from their salary for the interest and fees 7 years later the loan amount just keeps on increasing instead of it reducing as they have been deducting for years every month and have never missed payment.

R2600 every month for interest and fees but instead of the amount reducing it has doubled last option is to report such to the banking Ombudsman