Credit Payments which I suspect they aren't alloca

It saddens my heart to receive phone calls telling me that I have not been honoring my payments which I did without cease. This morning I got a call from Nedbank's Lawyer telling me that he was instructed to sue, for what I don't know. You know this makes me not to really wanna involve myself ever again with Nedbank since their services are very poor. I made an agreement with them and their lawyers that I will pay them monthly R1500 which I do but it shocks me that they want to sue me now for what I don't know. Can someone from head office look into this matter because me I am done with Nedbank, just waiting that I finish paying off all my commitments I have with them. Never again will i put myself in this situation again. i have learnt my lesson.