Poor customer service

I processed an upgrade on my Cell C contract on Saturday 27-06-2015.My package was changed from a Straight up 50 to a Smart chat 1GB. I received my new device and was told that my sim would be activated after 2 hours. I then decided that I could use free minutes as opposed to data and called to try to the store to find out if I could have my package changed. <br> <br> I tried calling 3 stores on Monday, 27-06-2015, The glen, alberton, southgate, all with no answer and finally managed to speak to someone at Newtown junction. I was told that I could call the call centre and have my plan changed. I tried calling 084140 and 084145 more than 8-10 times, but I kept getting redirected with the voice prompts and never put through to an agent. I then called the head office and managed to speak to a consultant who said that nothing could be done until 3 months had passed, but she seemed unclear. <br> <br> All I want to know is whether or not my plan can be changed, and how to go about doing it.