Extremely bad service and feed back

For about a week my father trying to get hold of MTN Head office, after going in and out of MTN stores in canal walk trying to settle a payment profile which no one has notified him about and no one wants to get back to him. The staff at MTN Says they cant help him settle the payment and he should contact head office but how can we contact head office when every time my father contacts them and that's on a daily bases he gets cut off! What type of service does such a huge company offer. They want you to sign the contract but after service is so ****!!! And staff lazy to get back to you<br>