CHARGED MORE THAN THE CONTRACT I SIGNED FOR

I took out a contract on 4th July 2015 for 1 gig for R99.00pm. There was no limit set and the Wi Fi was supposed to stop working and warn me when the 1 gig was used up. After 1 week, I wanted to check the balance for interests sake and went to Cape Gate, where I was told that I had a bill of over R2000. I went straight down to Willowbridge (where I got the device and contract)and the chap there logged a query on their system. This was on the 11th July 2015. I was told I would be contacted in a day or 2, it is now the 22nd July 2015 and to date nobody has contacted me to sort out this mess. I did not sign up for anything except 1 gig for R99-00 per month and that is all. If the info was not set up properly or there is a glitch in the system is not my problem. I will be debited with over R2000 at the end of the month and I want this sorted out and and the contract cancelled before the money comes off my account. I have no desire to deal with a company that has such poor customer service. I also have the number of the supposedly Regional Manager and have left 3 messages for him to contact me to no avail. His no. is ***, ( Eugene) My acc no. A***.