African Bank ripping of pensioners

My dad made a loan of R15 570, 13/12/2007 the loan was suppose to have been paid up 01/12/2010 with an installment that they paid of R793.69 month while my dad was still working which they did pay until my dad could not work anymore then short payments was made but my mom still made payment maybe less but she still paid to date they have paid R28 721 which according to African Bank they still outstanding with R4145.58. Which tells me my mom has paid this loan long time finish with interest so why are they still outstanding. And what African Bank did now is they started debting their Standard Bank account which does not have money in and interest is being put on the account the amount of R793.69 for a pensioner?? I am not leaving this matter as is next will be a email to the ombudsman I Denise Adams has gotten power of attorney on all my dad's affairs his Mr John Charles Petersen account nr ***. And before calling me make sure of your facts and look on your system.