'Missing Data - More Like ******'

I have a 4G Wi Fi router that I use when not in the city. I would normally use 5GB in a month and concede that I may have used more in this past month. However, the last two weeks have seen data just being gobbled up - sometimes having to purchase twice on one day! Considering that I have a history of past use, I know that this cannot be correct. On top of the 5GB bundle that I get every month, I have had to purchase as follows: 10 Aug - 3GB, 12 Aug - 4GB 17 Aug - 3GB 18 Aug - 4GB 19 Aug - 1GB 21 Aug - 2GB This is outlandish. I have logged a complaint - reference number 1- ********** ********** last week, but still waiting for someone to come back to me. This means that i have gone through almost 20GB and the month is not yet over? I do not download movies etc - just email and a bit of Facebook and have never had data disappear at this rate. I have a feeling that Vodacom have been depleting it unfairly. I will be looking at alternative suppliers which is sad considering I have been a loyal customer for 12 years.