Invoice issues

I am a customer of Cell C for almost 10 years now. I recently took out a data contract and to my understanding it was supposed to be R170 per month for 3GB anytime data and 2GB night data. <br> Last week I received my first invoice via e-mail. At first, I was not even going to check it, because I know it will be R170. But to my surprise the payable amount is R2496.47. Call charges of R2000!<br> I registered to check the details online and got another shock: the invoice amount for April was already at R2500 too (halfway through the month). Now for April I've used 2,64GB of data already (from 3GB available), so how on earth can my payable amount be R2500 already??<br> I went to a local Cell C store (at President Square in Krugersdorp) where I always get the best service ever. The lady called your costumer care line but the situation could not be clarified. I was told this is an open line and I just used too much data that I was charged for... 1.I did not ask for an open line. 2.I was unable to connect to the internet from the night of 28 March. assumed that reached my 3GB cap or pro rata.<br> Attempts to make contact via email was unsuccessful and I'm not going to make another call...