Not very clear what you are doing, you have the laptop connected to the TV as a screen? But your WiFi on the laptop does not work when it's connected to the TV? That does not really make sense, the video connection and WiFi are separate hardware. WiFi is working, you connect laptop to TV and WiFi disconnects? or what exactly are you doing and what is happening? What exactly is this dongle you are using? That is a generic term for pretty much anything you can attach to something.