Vodacom has no security against theft of my account.

My cellphone account has been hacked and someone bought a wifi router with 10gigs data on my account. This happens, and I understand. But I asked what can I do to make my account safer and what Vodacom's security measures are, and they just said that they don't know. There is nothing they can do. So now ********* are *****ing customers' accounts and buying whatever they want and Vodacom just lets them. They did cancel the order at least. But if I was out of the country or didn't check my messages, there would have been no way I would have realised this.