NSFAS does not want to stop debit

NSFAS paid for my university fees for 2 years, from 2***. In 2015 I was called to start paying for my Dept which was R 41 731,99. Every month R700 was deducted from my persal number since 2015. Today I am still paying that amount which indicates that I'm being ****** as 2015 is quite a long time even with interest included it does not make sense. They do not answer their telephones, with no clue and helpless on getting hold of them. Please kindly assist.