Bad treatment by ON airtv

I bought an Explora DSTV 3or 4 week ago ,the time I bought this I asked the person whether I will get the Public Channels on that she said yes but it is not true.5days ago I called ON airTv personnel to tell that if Public Channels are not available on that Explora I do not need it they told me that I have exceeded the days for cancellations but on several occasions I tried to contact them I did not get hold of them.There was a time when I called them they said an agent will contact me it never happened.During that time I was still having time to cancel it but they decided to delay the process, even today no agent has never called me.