Account overcharged-Account number: I***-2

My monthly account is normally anything between R2 000 to a Max of R 4 000. In August 2015 my account was abnormally billed to R 11 223.52 of which this was apparently data charges. I logged a query with Vodacom on the 11th of August, they sent me the data report of which in it I was charged R 6 554.07 in just a day worth of data, the following day exactly R 1727.43 was also charged. I do visit any internet sides as I have a 3G modem with Vodacom. During the day I am on my Employers WI-FI. The response I received from Vodacom was that I should check my settings. I insisted and eventually they informed me that as \ a valued customer"they will give me a \""once off gesture of goodwill"