Text on Moto X 1st generation does not turn when phone turned to horizontal. System upgraded in last week
Go to settings—>Display—>Scroll to “When Device is Rotated”—>setting should be “Rotate the contents of the screen”
Note - Some apps are written to stay in Portrait & not in Landscape.
Also, while most (but not all) apps will rotate to landscape mode, the home screen does not - it is always portrait-only, regardless of rotation setting.
My Moto E home screen flipped. There is a setting to make the home screen on my Ascend 5w hurried you n the menus as well.
Different home screens have different options. Some more simpler ones may have have the option.
Do you know if the phone isn’t rotating at all or is it only specific apps?
One other idea that I used to give out is to check the phone’s gyroscope. On some older phones, the gyroscope may have failed so the phone doesn’t actually know that it has rotated.