Incompetence from Cell C and Nonkululeko Nene

I would like to express my utter disgust with the Cell C Team and how they have treated my mother, a client of theirs for over a decade. My mother had upgraded her contract in October and the total amount was agreed upon there and then. She then contacted Cell C to confirm the total amount that I would need to pay as they refused to load on my banking details as I will be paying it for her. The app showed a zero amount and the consultant confirmed that we would be paying R329 as initially agreed upon. We have been in a constant battle with Cell C for the past 3 months, my mom's service gets suspended and she is made to feel like a ***** for having an apparent "outstanding amount". Last night was the final straw, every time we call in we get told there was a ticket opened and it is still under investigation. After much screaming and shouting yesterday, we were transferred to a so called manager Nonkululeko Nene. Absolutely useless! She refused to see our point and kept throwing it in our face that "THE SYSTEM SAYS YOU ARE OWING" So now my mom's service will be suspended until they are done with the investigation. This is the biggest load of Bull**** i have ever come across. How long does it take to investigate incompetence? We need this resolved today!