USELESS MTN

I am with MTN for as long as i can remember. They are lately completely useless. I have 3 numbers with them of which the contracts have expired , i am trying now for 4 months to canceled 2 0f the numbers with no joy but i pay every month for them. You can send them mails they do not reply try and phone the you will get a message they have net work problems . I have down load their app that also means nothing. The app tell me my account is R466.00 i received a sms my account is R1393.00. I SEND A MAIL TO THEIR COMPLAINTS DEPARTMENT NO RESPONSE .Now they have suspend my services again with out notification. How can you make use of their services if there is no way you can hold of them.