How to lose a satisfied customer within a few months

I have been a satisfied customer of Vox for a few years. The fatpipe was inexpensive, it worked and we had good support. Then fibre came and from there it all went downhill. I accepted a fibre agreement in November last year and part of the agreement was that I would pay no monthly fee like previously and would get 1 Tb data until the fibre is up and running. However, I cancelled my Telkom ADSL line too early and could not use the data, but it was mostly my fault. Then I still kept receiving invoices for the monthly fatpipe agreement. I contacted the marketer, Morne Coetzee, who assured me that I do not have to pay and that he would take it up with his manager and sort it out with the accounts department. But the accounts kept on coming and every time he assured me he would sort it out immediately. I then, as an interim measure, also signed an agreement for the MTN Fixed LTE-A and it was up and running on the 26th of February. I was, however, still waiting for a statement that gave me credit for the amounts that I have been charged with for the previous two months. To my dismay, I received a suspension notice on Monday morning early as well as a final demand notice. To get them off my back I paid the outstanding amount immediately and thought we could sort it out later. At eight I phoned Morne and demanded a written apology from the person responsible for the mess as well as an account statement reflecting the credit due to me, otherwise I would cancel both the fibre and the LTE agreements. Suffice to say that I cancelled the agreements late yesterday afternoon. To add insult to injury the LTE service was suspended during the afternoon despite the payment! I do not expect that there will come anything from my complaint, but at least it made me feel better.