Shocking service

Following 9 emails, to 24 different employees, 41 phone calls and 3 text messages, I have tried to contact the GM, in order to have our switchboard attended to. We are a busy medical practice and the impact of not having a reliable telephone service is exceedingly difficult to maintain. We have been without a telephone service since Monday morning. What else do we need to do to get service? Why should it be necessary for a client to go to these lengths. This has to be the worst telecoms company we have ever dealt with.