Mtn ****ming us on data and minutes

Mtn is robbing people of their minutes and data ,I have laid a complaint with them and they did give me their reference but when I called to hear about my issue because 72 hrs of response had lapsed I was told that the call was closed . I have 50 minutes of any time calls but I used 25 and my phone was already alerting me that m out of airtime. Last time they did that with my data of which they continue doing it and blaming us that it's being eaten in the background of which they are lying ,I switched off my data but still it finished fast,i don't have a subscription ,nothing but 40 gb finishes in a week ,when I buy my own 10gb it lasts me almost the whole month ,Mtn is a **** company and I hope people on contracts should be aware of it ,I think I should just leave them and opt for Vodacom .