Cell C, my worse nightmare ever!!!

Good day No words in the dictionary can describe my frustration with Cell C! I cancelled an upgrade in October 2022, after months of complaining, escalations, emails etc. the issue was finally resolved. The consultant by the name of Nhlanhla S assured me on the 23/01/2023 that my problem was resolved and that I will be put back on the month to month contract which I was on prior to the upgrade. I even received an SMS indicating that my query for case no *** was resolved. Low and behold, Cell C disconnects my line today indicating that I ow them R582.73 when they debited my account on the 31 January 2023 for that amount! The audacity of Cell C to take my money and then suspend my line! They handed me over to the collections department and a useless agent tells me that I must pay an amount of R1300 for the upgrade that I cancelled. She tells me that is how the process is! she needs to be disciplined. I have emailed all proof of payments to Cell C (to B.Sibeko and Nhlanhla S and Cell C customer service) I do not want a response that an agent will call me, I want the upgrade to be cancelled, the debit order stopped for the upgrade that never happened and my line restored immediately as I owe Cell C nothing. This has been going on for months and it is now affecting my health!