Limit not enforced

About a year back I took out 2 data contracts with vodacom. I made one of them top up and I put a R50 limit on the other. But I've noticed over the last few months that this limit isn't being enforced and this month my bill is already R1650 on a R250 contract. <br> <br> What is the point of telling customers they have limits if these limits aren't enforced. And it's not like I went crazy with data usage. Last I checked I had 3 gig left and the next thing my bill is R1700 but my contract is still running. <br> <br> This is why I changed my cellphone contract to Telkom. As soon as these two are done I am moving them away from Vodacom. Worst network in the country. They don't give a **** about their customers and don't abide by the procedures they've put in place to protect their consumers. <br> <br> Does anyone know where I can place a formal complaint? Which regulator, oumbadsman, etc?