no internet connection and bad service

I have no internet connection on the cell c network for 3 days. Every time I phone the call centre, they say I must change the APN settings on my phone, as I did it. And it is still not working! Then the lady said I must change the network setting to vodacom! But it is still not working. According to Cell C customer care there is only a network problem in the Western Cape. I have renewed my contract a month ago with Cell C but now I get this bad service. Two weeks ago I have downloaded software like Whatsapp on this phone but the internet was working good. But a few days ago the internet is not working at all. Now suddenly it is the phone's settings!! I have send only 5 whatsapp messages...and 200MB is gone!! It is day light *******! And Cell C cannot give me an answer to that as well