MTN is the most useless service provider

I have registered with MTN to email my statements on a monthly basis. Since I took out the contract, this has not been happening. I keep calling their stupid call centre and it takes months for them to send bills to me. Worst of its kind, three weeks ago I called the useless call centre again to request my November invoice and I was told it is not available. I was told a call will be logged and I will receive my invoice within two to 24 hours. That has not happened. I need my invoice to support my cellphone expenditure claim and if I don't get it by 2015/12/01 at 15:00 I will forfeit my expense claim. I have called the 808 number again on 1/12/15 at 12:15 and have been holding until 13:00 only to be told that I cannot get my bill because my query has not be freaking atttended to by billing. I think it's time I jump ship. Cell C do buy one out of their contract. I am tired of this useless service provider.