Cant make calls for over 3 weeks now!!

firstly the upgrade they omitted extra units charge ( which Ombudsman got them to correct) and I received my credit ( after months)<br> <br> my phone not working for over 3weeks already and no one can tell me why I cannot make calls<br> <br> now main issue is that I cannot make calls, have not received any data and less airtime per month.<br> I also learned through the store that I have been down-graded from MyMTN 200 to MyMTN100 minutes at the same monthly price of R549 ( like really?)<br> At first they said it was my phone physically with a problem, then claimed was my sim card, but if I place another sim card in the phone, it works ( that eliminates my phone) then if I place my sim card in another phone still does not work, that eliminates the sim card.<br> They later said was the NETWORK which till today it is not working.<br> I am told to settle out if I want out of a contract: this is a contract which is not working, why should I pay???<br> <br> I am tired of this company seriously!!!!!<br> bad service with staff who keeps referring me to different people and departments. even the store at Canal walk has given up on them as they cannot assist me!