Beware! Phantom Data charges - Corporate *******!

My average cell bill is about R1500 (with data usage at about R 500 max) - then suddenly I get a bill for R4900 (with a data usage of R 2700)! So in a total state of shock, I call Altech to find out what happened. NATURALLY they have NO idea what data was used and asked me to fill in a form to send off to the 3rd party to request a breakdown. I fill in the form on the 23rd Sep and send it off - and again on the 28th of Sep because I heard nothing back). I'm still waiting for a response!! In the mean time I pay my R 4900 bill (SO begrudgingly) and get the bills split so that if there are future PHANTOM charges I can just NOT PAY the cell bill in question. To my absolute disgust (picture me vomiting in my bag!) I get a threatening sms from Altech that if I don't pay them an additional (where the hell did this come from) amount of R650+ then they will suspend my account! There are apparently NO MANAGERS OR TEAM LEADERS actually doing any work there today because after being hung up on by an agent I called to speak to a senior person and nope - no one there... Then I asked to be put through to billing - WOW Trudy... if I dealt with MY customers the way YOU DEALT with me, I'd be jobless