Upgrades and cancellations of contracts

My contract came to an end I did not cancel which Because I did not explicitly say cancel the contract continues regardless although reaching its full term. I then decided to upgrade which should take a week or less.. I told the numerous consultants to reach me on my prepaid number for confirmation of anything yet when I enquired after two or three days I’m told they tried calling on a number I advised was not in service and had lost the sim card. Two weeks into the upgrade and following up I am advised the upgrade has been done but the items requested is out of stock which I was not made aware of. I reconsidered the upgrade and now want to cancel.. I called the *** number and I redirected to chatbot and sms channel which do not help me anything and suitable for prepaid users. I went to Vodacom sumnypark pretoria and was told I can’t do cancellations instore I should call the same number that takes me to chatbot and doesn’t help. At this point I want to cancel everything I can cancel with Vodacom and want someone to reach out or have a way that I can reach out.. this is just one issue apart from someone changing my payment to cash from debit order making me miss my payment