Problem with build.prop editing

I used BuildProp Editor from Play Store to optimize several things but when i used it to edit Android version, it doesn't seem to be applied (?). In About it still shows 5.0. I used ES File manager to read the build.prop, it says Android 7.0, so it must be saved.
I'm wondering if all my changes in this file was saved or not. Plz help me

Attached Thumbnails

       

from xda-developers http://ift.tt/291EiqI
via IFTTT