Night surfer data problems

I have had problems the last two months, where I try to use night surfer data after 12 it uses my normal usage data, i called the call centre and they responded by saying that my modem is on roaming, I then set it up to not be on roaming, I still have the problem my nightsurfer is not working, I went to Nelspruit telkom riverside branch on saturday to explain to them the problem and took my router with, biggest mistake I made nobody could assist me and the technician there did not have any facilities to check my modem and the staff had very bad attitudes telling me that they cant do anything, I dont knw what to do anymore because I have tried every avenue with telkom and nobody can tell me what the problem is, I am paying for data that I dont get it is unfair and disgusting the way you treat your customers you should be ashamed, I want answers there is a consumer protection act, and I will cancel my contract .