It won't let me select anything, tried reopening it but still nothing, also tried power cycling Xbox and still nothing.
Hm, you shouldn't ever need to hard reboot the console to fix it. I've had the issue countless times, and have never fixed it by powering off - just quitting the game at the dashboard/home screen (press Start over the windowed app/game running, then select Quit, then relaunch Elite).
It won't let me select anything, tried reopening it but still nothing, also tried power cycling Xbox and still nothing.
Opening the system map with head look toggled on can cause it. I can reproduce it on a regular basis.
Depending on how often I am in and out of the system map on a given night, I'd say it happens three or four times a night. It lets me pan around the map but not select anything. Leaving the map and toggling head look usually fixes it for me.
Your mileage may vary