Bad service from MTN

Good day. I got a call from MTN for a promotion I was never with MTN before so I thought let me take the R59 one for my son to download game on his tablet if he wants to play,they gave me 1month free trail where the next week I received emails saying I am owing them R399 for updates,calls that has been made for hours and ever since my 1st week I have been trying to call them where no one assist me,they deducted from me R460 the next month..let me just add the Sims are not rika so I don't know how and where my son only downloaded 1game and never again,as to the schools began. For the last 3weeks I tried calling emailing like crazy and where I get no service no assistants for something I did not apply for,and the first time when I eventually get throw to them I get someone telling me is it not an upgrade where I said "Mam this is the first time for me being with you and I am with vodacom' where I get a rep**** for sorry mam I can't help you then and she put the phone down. By the end of this month I will be paying for something I did not apply for and I even went to MTN shop where they told sorry they can't help me..if nobody can help me what am I supposed to do? This is the baddest service I have ever received and nobody can give me an answer but quick to withdraw money from your account..