It sounds like your port is "Dead", You need to find out where the wires from that wall jack go so you can plug the end of it in to your router. I am guessing if you have multiple Ethernet ports throughout the house. They should all go to a central location, Usually a closet, basement, laundry room, maybe where you heater or AC are. Somewhere away from the main living area. That is where you need to setup your router or a switch to plug in the end of the port you want and make it active.