Network and no signal

I have being experiencing bad signal for awhile now so it has taken just short of a month to get a technician to come and see that there is nothing cell c can do now i try and get hold of a manager in the business department but this is a useless process as all i get promised is that i will get a phone call shortly that never happens, it has got to such a point that i record all my phone calls to prove how pathetic the call center is. The bad signal however is affecting work and now that my calls are recorded i have proof that i might loose a project due to as i quote " You are very unreliable and can never get hold of you when needed" this is not the first time that we are experiencing clients complaining either.