Aspect Ratio problem

Hi all. In my app there's a section which use can set what kind of aspect ratio he wants the gameto use. I'm Testing my app on my Galaxy S5 which its aspect ratio is 16:9. But the problem is when the user sets the aspect ratio to 16:9 in the game's setting, some parts of the game gets clipped. (e.g GUI and some cubes) Any Ideas how can I fix this?

Using Unity3D 5.2 Pro