A:Answer You can set the Game mode as (ON, OFF or Automatic), if it's set as automatic, the TV needs to recognize your device (Console/PC/etc) and it will turn ON the game mode ONLY when a HDR content is displayed, so, I (personally) recommend to set as On if you're playing games and don't want the TV trying to recognize the content.
Note: Don't forget to active the Anynet + (HDMI +CEC) and Input Signal Plus on Settings > External Device Manager