Quick to grab your money, unwilling to rectify their mistakes

I did a telephonic upgrade with Vodacom on 1 August. This happened within 30 minutes and 48 hours later, the device was delivered. Only to discover the incorrect upgrade was done. Since then, it has been up to me to get the issue resolved and the new contract cannot be cancelled until they collect the device. I have been struggling since 4 August to get this resolved and 4 weeks ago, they logged a call to get the device collected by RAM. And nothing is happening. I'm following up weekly, now daily, and still, no action. I was even told to wait 24 hours, and when I followed up after 24 hours, I was told I must be more patient. In the meantime, they are collecting money for this upgrade. Why is it possible to organize an upgrade within 30 minutes, but takes more than a month, to organize a cancellation and collection? And why must I put in all the effort to get this done? I get the idea that Vodacom is hoping that I will eventually just give up, and accept the new contract. My original order number is K***. And the dispute case number is RCO257936. I have been communicating via FB Messenger with Vodacom, but still, no joy.