No Connection

A few months ago my internet connection ceased to exist. One computertechnology schooled housemate of mine could almost immediately tell me what the problem was. So I called our lanlord to tell him the problem ( so that he could get it fixed), he told me to contact the firm that did the internet connection installation. They tell me to contact the helpdesk, Helpdesk confirmed the housmate's analysis of the problem and tells me to call the disturbance service. Disturbance says that our house has an internet connection and that the problem must be local, meaning; a router-computer connection failure. Which is as much as I knew a month ago. All this time relying on contact with the outside world via internet connected computers available at campus. But who can I call to fix the router-computer connection?