Vodacom Data Charge - ****************!!

In all my years of being a Vodacom customer, NEVER have I had a bill of R9000+!!!! I have brought up the issue of being charged excessively back in April and May of this year. My account number is QC387841 and my reference number is 1-3 ********** 84 3437. I have been a long-standing customer and have data limits set in place on all three of my lines, yet I'm being charged thousands of rands for data. I have been told that a limit is not guaranteed which I do not accept. I sent an email to your complaints line and had no response. I am extremely unhappy and have had my credit score affected by this issue.