Beware of signing LTE contract

I've been trying to resolve my problem with my data usage for almost 2 weeks now. All I get from telkom, that's what I have used and that's it! The more I explain to them that I need a clearer answer, they say there is nothing they can do about it. For over a year with another supplier, I never used more than 7gig data per month, now suddenly, moving to telkom, I use 10gig in 14 days. When I enquire about upgrading, they say I can't, I have to wait 3 months. I want to cancel this contract as I spend more time getting assistance and data than what time I can utilize to work. Between them and mobile talk, I've waisted two weeks of work and I'm nowhere further than where I was. They say I have sufficient data left, the data I have left is for wifi hotspots and night time data! But they still can't answer my question.