Excessive billing for internet usage

Hi<br> <br> I have registered a call for excessive billing on my MTN account for June and July, most probably August as well.<br> <br> I am on a 500MB data package per month and because the signal of MTN is so bad, I use WIFI at home (Telkom ADSL), which my phone is connected on. So I minimally use data on my cellphone.<br> <br> I have been on the current contract from January and only recently, in June I started to get excessive billing for internet on my cellphone. Which I do not understand. So I logged a call/query on 27/07/2015 via email (call# ***4). Got replies from<br> 1. Simphiwe Thwala (07/08) telling me to visit a store for explanation???<br> 2. Mbali Moloelang (13/08), telling me to get itemised billing. But that report does not give detail.<br> 3. Glen Motladile (18/08), same response as Mbali.<br> <br> I then called customer care on 28/07/2015, spoke to someone called Ayanda. She gave me another ref nr ***. No feedback received on that.<br> <br> I also send a message on Facebook on the 6th of Aug. No one person answers me with a positive response, but I did give a clear message of the problem initially. Got responses from a Devan and later a Bongani, but only asking for my cellphone nr and if I was assisted.