Follow these steps to restore it back to the fullest aspect ratio you can.
- Right click on a blank spot on the screen.
- Select Graphic Properties
- Choose Display
- Resolution - change to 1920X1080
- Click Apply and OK.
Your screen should now be maximized!
Note: I put my screen resolution as high as it would go. Your laptop may have this exact same setting. My recommendation is adjusting the settings to the max!