absolute worst service ever

I Took out a tablet contract stating that I only want to pay the advertised price of R199 pm. After a week of getting the tablet I was informed that the bill has accumulated to R1300 for the month. I told the sales consultant on taking out the contract that I didn't want an open line, as I DO NOT WANT TO PAY MORE THAN R199. After almost 3 weeks and 100's of calls (from my side) nothing has been resolved and its been a fight from the start. I have been a loyal customer of Cell c for many years and my have 2 open cellphone accounts which have never been abused or unpaid.....if this is the way they treat their customer, seeing that i'm also in sales, I most certainly do not wish to continue with them. I will not leave this here and will continue to tell as many people as I can about the pathetic service rendered. Very upset and disappointed customer!!!