fed up

Every month I receive my invoice from MTN via email automatically without me having have to call them. The last time I received an invoice from them was in October. For the past 3 weeks I have been on the fone with them requesting my November invoice as I need for work purposes. Today is the 10th of December and I still have not received anything from them and even when I go to their website it has not been loaded on the. I am sick and tired of calling them and now just frustrated by the whole situation, surely sending an invoice to my email cant be that hard but they are failing to do exactly that. yesterday I foned them again and they told me to wait for 24 hrs. I have been a client of MTN for four years now but they don't value that...somebody help before I completely loose my mind. Im due for an upgrade and im so not upgrading with MTN im just waiting for my contract to expire so that I can go somewhere where ill get value for my money.