Why would i be expected to pay for no service

The Wi-Fi has not been working for over 2 weeks. In the interim, several technicians have called to arrange an upgrade of some sort. Of course, nothing has happened, and the Wi-Fi has still not been working. Why would I be expected to pay the full monthly amount for a service I did not receive?!<br> I have incurred a considerable amount of unforeseen extra expenditure for data that I had to purchase. Who is liable for this?<br> Furthermore, after numerous calls and self-service logging of enquiries, no one has called back.<br> I wish my account to be adjusted accordingly, the service to be repaired and/or an alternative to be offered in the interim.