MTN is misleading their customers!

I have 5 sims/2 x phones on my contract. When I check *141# on my 2 phones they show I have 4gb of data available yet when I use data I get the message that I'm using 'Out of Bundle Data'. I have queried this with MTN call centre and with Waterstone branch, who told me to ignore the message, and I even raised a complaint (MTN Req:***) for which I have not yet received a response! My service was subsequently suspended then I received an invoice for almost R2,500!!!! Again went in to Waterstone and was kindly assisted by Marius but MTN's explanation (Req: ***) is that this data is for Simphy and is not 'proper' data, but *141# does not show this, it still show that I have 4gb data. I never asked for Simphy and don't want this....I have been misled that I have data yet am being charged for it despite the fact that I have tried to find out what is going on but their agents don't know their work nor do they respond to my complaint. It is unacceptable that I now have to pay for MTN's incompetence!!!