VODACOM DATA JUST DISAPPEAR WITH SHOCKINGLY NO ANSWERS OR EXPLANATIONS!!!!?????

<p>During the past 3 Months i have contacted Vodacom Numerous time, Visited few branches in search for answers regarding my Data on both my phone AND Mobile Wifi Device that JUST DISSAPEAR??? According to Vodacom im using DATA...UHM i know that it is a mobile Wifi device but where to does it dissapear? I have gone through 15 Gig only this month - by checking emails, using google and sometimes going on Facebook or Twitter (and iam not a big social media fan). My Mobile Wifi device are loaded with 10 Gig a month, but between 9th and 13th each month 10 gig is finished. I Hotspot through my tablet and after 2 days 3 Gig finished again, i buy ne 3 Gig and after few days finished, i uplaod 1 gig and after day its gone... How is this possible??? No one at customer service or outlets is able to help me. The are happy wih my laptop, ipad and iphone settings (i checked it to make sure its not my phone\laptops\ipad problem). Previous months my account wat R3000 and all Vodacom could sy is DATA....One person using almost 16 Gig per month - NOT POSSIBLE. After the sales perwson assured me 10gig would be more that enough for mobile wifi device...EMPTY PROMISES and now my sky hig account is my problem??? I am discusted with Vodacom and will definately NOT make use of their service (damn expensive service) again if it come to upgrade... </p>