Playtesters having weird resolution issues

I have a playtester who is having a lot of issues with my game in full screen.

Here is what my game is currently doing.

DefaultGameUserSettings.ini

[/Script/Engine.GameUserSettings]
bUseVSync=False
//ResolutionSizeX=1920
//ResolutionSizeY=1080
//LastUserConfirmedResolutionSizeX=1920
//LastUserConfirmedResolutionSizeY=1080
WindowPosX=-1
WindowPosY=-1
bUseDesktopResolutionForFullscreen=True
FullscreenMode=0
LastConfirmedFullscreenMode=0
Version=5

And in the Game instance bp I am setting it to fullscreen.

Here is what my play tester is seeing upon opening the game:

This is what it should look like: