Misrepresentation in contract and omission of finer details

I recently upgraded with MTN and made a decision to take a tablet. From the word go I had challenges. Firstly no stock. Eventually stock arrived I received the tablet Nightmare begins agent never told me all tablets is data only never advised me still waiting for voice recording as I am disputing the fact as I am pretty much sure I asked for voice and data and if I was properly adviced would have made a better decision as I need to phone a lot Second nightmare. Received end of June bill of r1886. When enquiring was told its early upgrade penalty. Was never informed that if I upgrade before the 24th month that I would be penalized. I upgraded may to avoid penalties and I asked the agents specifically if there would be any penalties to which he responded in the negative. These two complaints is hanging in the air for almost more then 10 working days without MTN personnel getting back to me