Airtime theft!

I'm disgusted with Vodacom and the way they rob their customers on a daily basis! I bought my mother a simple vodaphone, thinking she would enjoy a bigger screen compared to her old nokia. Especially being a pensioner. But my poor pensioner mom spends a hell of a lot of money on airtime!!! Today I bought her R29, after 5min on the internet she only had R8 left! How is a pensioner meant to know to convert airtime into data??!! And with her R8, She couldn't afford the lowest amount of R9! She also bought R15 yesterday, and who knows how much each day before that.This is possibly the 5th person I've heard complain about vodacom ripping them off, this month alone. And when you call them, the excuse is \you probably have applications running in the background". My friend lost R50 airtime. And you people have him a measly 10mb free. I've trusted vodacom for years"