They want me to pay Prescribed debt

It's been 3 years since I had been listed. I Called the JHB branch, was sent to the no *** apparently it the head office, but rather collectors. I asked for the Prescribed letter since it's been 3 years. instead, A lady by Alezen or something told me I took up the money I must pay. I told them I know that it's prescribed and I would like a Prescribed letter, she then told me she's not by her desk she will call me back, but it's funny I was transferred to her line.

They acting as if I don't know any law whatsoever and they can just trick me.