The guide data update can take a long time to complete, and until it finishes, the guide info in Live TV, and other categories will be blank.
Don't trust the guide status in the settings page.
During the guide update, click on the hamburger icon (3 horizontal lines) in the upper left hand corner of the settings window, and you'll see a progerss bar, like this:
My guide data update usually goes thru 2 consective download sessions before it completes.
If your guide data still doesn't populate, try changing your location to a ZIP code near you, rescan, and add to guide.
Again, wait for the guide update process to complete.