Impossible to reclaim credit after a run-around data contract cancellation

Unfortunate to need to move to another network due to Vodacom's ineptitude after having been a customer for over 20 years. Just a litany of issues at each turn in trying to not have a data contract auto-renew. Turns out you have to call to communicate the instruction to not auto-renew at a very specific day, outside of which you're either too early for Vodacom to action it, or too late to not incur another month's fees.

After eventually stopping the contract from continuing after it had run its term, I was signed up for a WhatsApp bundle which I didn't ask for. Then, it turns out I have a R500 credit balance in the account which is now locked up for eternity. Without exaggeration, I must have spent on hour on the phone to various consultants and people at the collections department to try figure this out. Now, I'm absolutely stuck because I can't get through to collections on *** because my ID number is apparently invalid, customer care aren't able to do anything, and there's no route to speak to a human via the WhatsApp support channel.

It really shouldn't be so difficult for you, but somehow, I've presented Vodacom with an insurmountable challenge, and its time to concede defeat and move to another provider.