Outrageous out of bundle charges

I have a 2GB MBB 24 month - Contract with Vodacom. It has always been a "Top Up", meaning that when the 2GB is finished, it is done, and you have to go and purchase a data bundle to top it up.

Suddenly this month I was billed 6,414.51 in addition to the R95 that this contract costs me. I have NEVER paid more for this account.

I called and informed the consultant that this has to be an error and it shouldn't happen on a top-up account, and in addition to that, there is no way that much data could possibly have been used as far as I know, but I was told, well it shows on our side so you must pay.

I feel this is Vodacom's error, as that ****le should NOT be allowed to go over the 2GB allocation, which is what I signed up for. I'd like to know when that condition changed, and I'd like to see a contract that I signed saying it could go over the contract amount.

Very VERY dissapointed in this blatant rip-off by Vodacom. I've been a loyal Vodacom customer for over 18 years, but I see that changing pretty soon as a result of this!