Poor Service From Vodacom, Really Poor...

So I've been a vodacom customer since 2016 (contract) and I have previously upgraded my contract with no issues and I am generally happy with the service that they give...However, when I tried to request for a new contract for my dad (because he NEEDS a new phone) I was declined because vodacom aren't happy with the way I conducted payments on my account. Context: In December 2017 I asked vodacom if I can make an arrangement to pay for both December and January on the 25th January 2018, which they agreed to do (keep in mind my account has always been up to date)...So on 25th January 2018 I paid for both Dec and Jan in cash at the vodacom store located at Cresta shopping centre. After payment was made, I asked the lady that assisted me if vodacom is going to debit my account. She said no since payment was made. The day after I had made payment, vodacom attempted to debit my account which was unsuccessful. The following month (February) vodacom added another R100 to my amount due and when I called vodacom to ask why they adding to my installment, they told me it's because I missed my debit order or that they tried to debit my account and it returned unpaid. When I told the agent that the lady at the vodacom store told me my account won't be debited, he said that I should go to the store and request for some type of dispute form to fill out etc. Now being the hardworking citizen that I am and everybody else, I simply don't have the time to be running up and down and because I'm paying for vodacom to provide me a service, one would assume you get what you pay for, meaning that vodacom could've at least send me the form via email to fill out and then I would've probably gone to the store and sort it out, but that didn't happen. I then asked the agent if there is anything vodacom can do and he said no (with no compassion or any willingness to help whatsoever) I then proceeded to speak with another agent from accounts and requested that vodacom no longer debit my account and that I will be paying in cash going forward because I don't want to incur an extra cost for vodacom's mistakes again.

So that basically placed a ding on my name to prohibit me from taking out a new contract with vodacom which is rather unfortunate because I always pay on time except when I make arrangements with vodacom which occur once in a blue moon. The funny thing is, is that vodacom want me to upgrade my existing contract at the beginning of May (4 months prior to when my contract ends)so that they can suck more money from me as I would have to pay for my current device until the actual end of the contract which is in August 2018, yet they don't want me to take out a new line? So that begs the question, does vodacom actually give a damn about their clients or are we just there to pay for 75% of services provided to us?