I called Amazon CS and they said it is a known problem and has to do with a bug in the latest release of the app. "They are working on it". I don't now why they don't re-release the old version until they get their act together
Having same problem with my 50UQ7070ZUE. Have gone thru various install, uninstalls, factory reset, reset internet, check software update, all of the supposed fixes that LG recommends you go thru. Just in Facebook messenger with supposed tech support for LG. It's like they all read off of the same flip chart. Very frustrating.