Vodacom's website is a trap for the unwary

I bought a 10GB per month data bundle from Vodacom. You are supposed to be able to check how much data you have used, to avoid the exorbitant out of bundle rates. For two months, I checked the website, and every time it showed that I had ample data left. I only realised that the website (or something else) was very wrong when I received a bill for over R12,000 in one month and more than R7,500 in another month. I tried in vain to work out how these charges were calculated, but the website is certainly of no use. Then I tried twice to send an email to Vodacom using their website, to query my bill, but after more than two weeks, I have not received any response at all. I am now looking for alternatives and I unless you want the kind of surprise I got, you are better off with another service provider.