To make it work, you need three devices; a Mac, a WiFi Router, and a TV. If any of these three devices are not configured properly, it might not work. If it doesn't work, we suggest that you turn off any VPN, firewall or antivirus apps on your Mac. Make sure your TV and Mac or on the same WiFi network. If you have a dual band router, use separate names for the 2.4GHz and 5GHz networks, then make sure that both the Mac and the TV are on the same network. In other words, if your Mac is set for 2.4GHz, your TV should also be set for 2.4Ghz. If the Mac is set for 5GHz, set your TV for 5Ghz. If you have a router with MAC address filtering, add the MAC address of your TV to the list of filtered devices. Rebooting your devices might also fix some unknown issues.