Poor Cell C signal, service and dialing line

Poor data connection and even worse signal to receive or dial out! As a matter of fact I can receive no calls at all for hours when I realize that I've got according to the pop up "Not registered on a network" whilst roaming. I spoke to a few consultants about this problem and Cell C Technical department with no success at all. This is affecting my income and is unacceptable! Cell C why do I have to pay R1500 per month, if this is the poor service and poor value for my money I get?