Poor Service from Cell C

Once again I have experienced the same issue with Cell C with no network since Thursday last week. Last month it was the router, this time we troubleshooted the same problem and it did not work. A call was logged with Vumatel, they called me and said everything is fine on their side and it is an ISP issue. I am really fed up and frustrated, Second month and i have had issues with this product, The customer service is appalling, nobody follows up and ensures that the problem is resolved. Also no refund for having no service combined this month and last month of 11 days, Cell C just get agents to phone you and no one with any authority to satisfy the client. I really want to cancel this contract, Worst experience of any Service Provider in S.A. Terrible