MTN cannot set my voicemail

When I changed from Contract to pay-as-you-go then my voicemail changed to Voicemail Lite, which means that you cannot set a message for callers and also callers cannot leave a message for you, MTN just sends me a SMS giving the caller's phone number. I have been to various different MTN branches over the past 3 months trying to get my voicemail changed from Voicemail Lite back to normal voicemail without success. I wait in a queue for about 30 minutes to see a \consultant"and tell them the problem. Then they reset my voicemail and I record a voicemail message. I then get a SMS saying \""congratulations you have successfully set up your voicemail\"". I then ask the \""consultant\"" to call me and test my voicemail. She calls me and the message she gets is \""Welcome to MTN voicemail lite. You need not leave a message as MTN will send your number to the recipient\"". They then log a call with the main MTN call centre and say it will take 48 hours and then it will be fixed. But it is not fixed. I go back in and go through the same thing again and still I cannot get off Voicemail Lite onto proper voicemail. Their system does not work and they don't know how to fix it! """