miss communication and bad reception

On the 27th October I purchased uncapped data for one day for R40 and the SMS I always get is to activate then by dialing *141*5# to activate, well I did the same, the option to activate was not there but I got the deactivating option well I thought they were activated and at first I used them the same day and they were not charging me from my normal data but later in the afternoon I noticed that something was wrong, I had my normal 1.179gig on my phone and I was left with less than 500megs whilebi had my uncapped data as my R40 was billed, I called their call centre which I hate to do because they are so unprofessional and rude and I was told that its not explained properly because mtn doesn't have uncapped data at some point I was bound to be billed at a certain amount those were words of an agent I spoke to, its not my first time using this type of data and when I reach 150meg I always receive an SMS that notifies me that I have used up my fair usage but I can still use internet at a minimum speed which I don't have a problem with that.I need mtn to tell me what to do, must I go to ICASA about this or consumer protection or what? I want them to refund me and I was miss informed.