Calls always going to voice mail

I have contacted cell c 3 times to log a network problem. When some one tries to phone me it either says my phone is of or goes to voice mail. After each network problem logged cell c has not contacted me i have had to contact them and the call centre person says that some one did contact me and they said my line is working. But now one has contacted me so some one at cell c is lying. I do not believe it is good to do business with a company that lies. I us this phone for bussiness, and am now battling to run my business because cell employees say they have contacted me but have not. ref ********** 067 ref ********** ********** 366 i do not understand how ever time you call they give you a different ref number either seems they do not want to help you. after having cellphone contract with cell c for over 10 years guess time to change............