I've got auto rotate on but the icons on my home page won't go to landscape when I turn my phone to landscape position.
I believe this is caused by One UI 3.1 and I'm just now catching it.
Solved! Go to Solution.
Press and hold on an empty spot on the home screen> tap the settings icon that appears ( should be on the right hand side) > scroll to the bottom of the menu and there should be an option that says "rotate to landscape mode" make sure this is enabled