Heads: I win, Tails: you lose

I finalised an upgrade deal with Vodacom via their online call centre. At the end of the call, we had it all nailed down: contract terms, device, delivery address, ETA. A week later, I got a bit jittery and made a follow-up call. I was informed that there was no trace of my order. In later calls, it became apparent that all of the interactions were logged, but that no order had been placed. I was completely dumbfounded. As I see it, I had no opportunity to renege on the agreement reached in that call, but Vodacom could apparently simply deny that it ever happened! I can't make any sense of that. Can you? It got worse, though. I have tried to get this matter addressed with a formal reply (an email, perhaps) at least three times now, and despite all assurances that my request will be escalated, I get nothing. No call back, as promised. It's clear that Vodacom has a systematic habit of simply ignoring anything it doesn't want to deal with. And I, a customer since before the turn of the century, have absolutely no recourse. How did we get here? This can't be right.