One line only - NO DATA ALLOWED!

I had my number on my dads name for 3 year put it over on my own name, for 1 year then when I want to add a data sim only they say no sorry we can not help!! only 1 line allowed!! So now I need to open a data account with another company!! this is my last year with Vodacom, always having problems with Vodacom and they have 1000 excuse!! Will move my 1 line to the company that wants to do business!!!