No assistance and lack of trouble shooting

I recently subscribed to a router on the 17th of March 2015, I got the 10 gig wi-fi promotion that comes with the device that uses the sim card of telkom mobile. After I received the device from the store I was told that I will get 5GB and pay pro-rata there after, meaning I will only pay for what ever data I have used. Fine, I understood that. Two days down the line my data (5GB) was depleted at a rate that I do not understand. I am the only user of the wi-fi and during the 2 days I have never downloaded anything to be considered a big file or anything like that, if ever attaching files for email and receiving emails is considered big by telkom. I then went to brooklyn mall, to telkom mobile, i was given dumb explanations like, my sim card was roaming?! and if i don't switch off my wi-fi device it still uses data even if my laptop is off, hence i told them they are talking ******* and i requested a query to be sent through. so today i get a call from a call centre agent who doesn't know jack ****! and I promise you telkom, if this issue is not resolved i will not stop writing to hello peter because at the end of the day its us, the customers who pay. query no: ***7