ASUS - ZenTalk

How do I get rid of this nasty button? Everytime I pickup the phone in an app I hit it and it flips my screen to useless landscape in messaging and browsing.   Makes me exit app and redo/restart what I'm doing, just to get back to portrait!  LANDSCAP...

I had to go to a black wallpaper to read or even see icon text. Resolution of most images now a fuzzy mess.Notifications are a useless stacked mess, no idea half the time what I'm being notified about. Had to disable all app and most system notificat...

How do I fix this?

Any ideas on why? How to fix?