Worst service ever and not willing to assist

Worst service ever! I have had endless problems with signal, I seldom receive and are able to make calls as there is no network. I complained to cell c, they checked the network and said it is not a network issue and that it is my phone and I must take my phone in to cell c to check. I took my phone in to Cell c and they said my phone was not a problem, it was the network. Cell C them went and closed the ticket saying it has been resolved. I then let cell c know that it was not resolved, they tried to phone twice, but both times there was no signal and they were not able to hear me. I then did not hear back from them. I now want to cancel my contract and cell c are insisting that I pay for my handset, which I do not have a problem with, but when working the amount out, I will be paying R100 sort of my full contract amount just to cancel. I then get told by the lady on the phone that only if the network team say there is an issue will they allow me to cancel. Clearly there is a problem here cell c. I have missed an emergency call because of NO NETWORK, and you wont allow me to cancel. Absolutely pathetic!