Even and odd pages always in different columns Writer

Version: Version: 6.2.6.2 Build ID: 1:6.2.6-0ubuntu0.16.04.1~lo1
When I open Writer I always have all text in two columns: first page on the right, second on the left, third on the right etc. It makes difficult to read long text. This appeared some months ago and I have not found how to get rid of it. I have tried to modify page styles and choosen “Layout Right and Left”, and the small icon in the “Page Style: Default Style” window looks like there is only one column, but when I press “Apply” my window is again in the position of two columns.
It makes difficult to read my text, because starting every page, I have to move the horizontal lift from left to right or from right to left.

Hello,

This post may help → How to Revert to Single Page View

Hello. Thank you! Sometimes you are like blind and cannot see simple icon, they are so many. Now works perfect! Hannu