Vodacom unable to solve our problem as they don't know how

We are currently experiencing problems with our phone. It has been a week since we lodged our first complaint with Vodacom in Kolonnade where we could not make any calls or use our sms services. No one was able to help us. We lodged another complaint on Tuesday 11 September where they told us that they will have it fixed within 24hrs. Yesterday when we phoned them to follow up, the lady who answered her phoned could not help us and promised to phone us right back. We are still waiting for Vodacom to fix our line as we still cannot make calls. This is a business phone, which means we cannot contact any of our clients.