Billing enquiry - Data charges

I was billed an extra R500 for data charges even though i still had data left on my data bundle. I called on 02 February to query this and was told that a data validation report is needed to find out where the extra data charges came from.<br> <br> I then requested the data validation and was given a reference number *** and was told that someone would contact me regarding the data validation. However, after numerous calls to the call centre as well as requests to escalate my query, I have still not been contacted.