No cell service

I upgraded my contract with MTN recently and this is where all my problems started. My phone receives phone calls but can not make outgoing calls, send sms or use data. I have called them countless times spoke to Jabulani, Themba, and Sibusiso they always adviced to switch off the phone and wait 2hours before I switch on. I have visited the main MTN Branch in Bloemfontein on 19/8/2015 where they did a sim swap and even that did not assist, I also visited the Mimosa branch on 22/8/2015 needless to say I am still experiencing the same problem for 2 weeks now. I have been told that my query is submitted to technical department and I will receive reference number sms but nothing came through.Nobody even calls back to ask if there is a change in my situation. I am truly disappointed in the level of service I have received from MTN after being a client for such a long time and I am seriously considering changing service providers. I feel they are breaching the contract by not providing me with service. All I need is my card to do everything now it does not do anything.