MTN have not responded to my problem since Feb2015

I am trying to setup my voicemail since I upgraded to a Samsung Galaxy S4 Mini.<br> It asks for a password which I do not have and have never had.<br> <br> MTN have not responded to any of my numerous calls and email. <br> <br> I AM GATVOL AND IF NO RESPONSE COMES FROM THIS COMPLAINT THEN GOODBYE MTN.<br> <br> Ever since upgrading at their request in Feb 2015 NO ONE AT MTN has been able to help me.<br> <br> I need to be able to use my voicemail urgently....