Telkom customer service is the worst

I recently did an upgrade with Telkom on 2 of my contracts. The one is Mobile upgrades for R99 and i am supposed to receive 1GB data on it, the other is 1GB FreeMeBoost for R149. I received my first invoice last month and the invoice is completely wrong. I am being invoiced for a Smart internet 1GB and a Smart internet 500mb. This is not what i agreed to, i had to pay around R719 on that invoice. I have opened a case at the Telkom store, i was told i would be contacted by customer care, this was 3 weeks ago, i still have not received any call to resolve the matter. The case number is ********** 0. I sent an email to the complaints department and they also have not given me any feedback. This is the second time i have had problems with Telkom when trying to upgrade or cancel a contract, this is getting ridiculous now, can they not do anything right the first time?? The minute you refuse to pay the invoice you are threatened with lawyers and being listed at the credit bureau when they are the ones that made the mistake. I am not going to pay another cent until this matter is resolved, otherwise they can just cancel the contracts completely!!!! I do not need this kind of stress in my life.