Nedbank harassment

I am tired of being harassed by Nedbank. A few years ago I lost my job and therefore fell behind with loan payments. 3 years ago I found a job and made monthly payment arrangements with Nedbank via debit order and have not missed a payment till to date. It started about a few months ago where I would get threatening messages saying their recovery department will send a sheriff for collection and I have a court date scheduled for my "UNPAID" loans. Now I'm getting calls on a daily basis from their recovery department which is really irritating. So what's the point of these payment arrangements if they keep harassing me like that?