Non-existent Service

MTN has the most useless customer interface I have ever come across. After following the prompts and selecting "0" to speak to a so called service champion I get told that I have selected an invalid option!! I have been trying to access my account for weeks now without success. Latest is that I have run out of airtime, yet when i check I still have over 400 minutes of airtime available. Obviously cannot contact the company to find out what is going on. I assume ***** to be at the bottom of this - the latest e-mail from customer care requested that I provide the type of information thath we always told not to provide to anyone!!!