OVER BILLING!!!!! Cell C R299 5Gig cap contract

I do not own a Cell C contract. But my sister does. My complaint here is simple and going to be direct. I personally will handle this matter with Cell C and should this go to legal, then im prepared. I want to make a public note to Cell C. My sister borrowed a R1,635.16 from me to pay this. She now received an invoice for R4,657.66. I want Cell C to give me a proper itemised billing. Correct your account. Please reverse the R1,635.16. I will be advising my sister not to pay the R4,657.66. Should you want to go legal, then communicate with me. We know the data was not abused for these months but this is ridiculous. R299.00 for a SMARTDATA capped at 5Gig. She does not stay 24/7 on the internet. if it switched off then it is off. Please correct asap.<br> <br> MONTHLY BREAKDOWN :<br> Jan - 01/01/2014 - R314.00 <br> Feb - 01/02/2014 - R300.50<br> Mar - 01/03/2014 - R299.00<br> Apr - 01/04/2014 - R299.00<br> May - 01/05/2014 - R299.00<br> Jun - 01/06/2014 - R299.00<br> July - 01/07/2014 - R299.00<br> Aug - 01/08/2014 - R299.00<br> Sep - 01/09/2014 - R299.00<br> Oct - 01/10/2014 - R299.00<br> Nov - 01/11/2014 - R299.00<br> Dec - 01/12/2014 - R299.00<br> Jan - 01/01/2015 - R299.00<br> Feb - 01/02/2015 - R1,635.16<br> Mar - 01/03/2015 - R4,657.66