Vodacom not responding to my queries

Hi ,I have phoned Vodacom on the 27th of August requesting to investigate my minutes usage and data usage as I have monitored it on my phone and it not reflecting the same as they charged me for .The lady informed me that they will log the call and sms the reference which never happened. I did however received an SMS to rate the service I got. Then on the 10th I did send a email to customer care for the same query and yet again I got no feedback. I also noticed that last year from October Vodacom started charging me for an additional 500mb of data per month which was not part of the packaged bundle I bought at the time of my contract upgrade . I am currently not happy. I also read on online media that this seems to be the norm as it just gets ignored when complaining about missing data.