Fed up with Cell C!

Very long story short: Was on a Pinnacle Unlimited contract, due to expire 22 December 2018. Downgraded to Pinnacle 1 GB Top Up on 14 November 2018. Apart from false advertising, numerous errors were made on the day, including additional transactions and migrating instead of downgrading the account. After being sent from pillar to post to get the errors fixed, I requested for my contract with Cell C to be cancelled on 21 November 2018 (adhering to the requisite 30-day notice). Instead, the Post Paid Agent (name can be provided) assured me that it isn't necessary to cancel the contract as he will personally see to it that I won’t get billed in error. He even provided me with his email address. I felt reassured, but it turned out to be empty promises. Balances and bill for December were still incorrect (dispute logged and confirmed, credit is being processed). I no longer want to be a Cell C customer and demand an IMMEDIATE cancellation. I have already cancelled the ‘downgrade’ and am NOT prepared to extend the 30-day notice period to January 2019. I trust all my telephonic interactions with Cell C were recorded and can be accessed to corroborate the above. Turning to social media to expedite the dispute!