No feedback on Data Charge

My December Invoice was R2459,41. that includes calls and Data usage. the Charge for data amount to R1741.91 of the total bill. Never, in the 23 Months that I have had my contract, have I exceeded R1100 for both calls and Data. My phone usage was exactly like any other month in December, I don't understand why there is such a big jump.<br> <br> I contacted Vodacom to dispute multiple times, I have been sent back and forth without any resolution. last week I was told they are still investigating and will get back to me on Monday. I am still waiting for their feedback, I am just tired of wasting my time on the phone without getting anywhere. Poor poor customer service. <br>