NSFAS is harassing me

As a former student, I'm grateful for assistance of NSFAS but I'm not happy with their service when it comes to paying back the money. They took my account to debt collectors and they call to harrass me for not paying while I've been paying. The statement from the collectors and nsfas don't correspond.

You need to sort this mess because we will end up suing you guys for false accusations. Please fix this I'm not owning R7000 my outstanding is R1900 or less, i want to settle it but you guys don't respond to calls. My email ***