pathetic call and technical support centres

I am a contracted mtn customer and have a problem with my voicemail. For months now I am unable to access my voicemail. When I call 100 or 120 The recording tells me the person I am calling is not available. I have called 808 who advised that I must reboot phone. Done, still not working. After more calls I am advised to call 1555 who told me the same, still no joy. 10 plus calls later technical now tells me this not their side, 808 only can resolve. Call 808 who keeps cutting me off after minutes of holding.... This is the second major issue I am having with this provider after they blacklisted my phone for months in error. It is redicilous that no one can resolve this problem which does not seem isolated on the internet discussion boards. Surely someone in their call centre or technical department should be able to resolve. I personally will not be renewing my contract or advising anyone else to make the same mistake I did to move from Vodacom to MTN. Pathetic