What is wrong with this LocalScript?

I was trying to Manipulate the Camera of a Player, when i made it to get fixed on a part it worked, but there was a problem with fixing it back to the Players Humanoid. This is the Code i used:

local Button = script.Parent

function close()
	if script.Parent.Value.Value == false then
		script.Parent.Value.Value = true
		script.Parent.Parent.Parent.LocalScript.Value.Value = false
		game.Workspace.CurrentCamera.CameraSubject = game.Players.LocalPlayer.Humanoid
		game.Workspace.CurrentCamera.CameraType = "Custom"
	end
end

Button.MouseButton1Click:connect(close)

Magically in Studio is working fine but when i run the code in Roblox Player it does not work, it just stops the camera where it is and does not moves it to the Player

The Developer Console says the following: Players.lehel55.PlayerGui.ScreenGui.Test.Script:9: attempt to index field 'LocalPlayer' (a nil value)

But the Player can be moved using WASD, just the camera is not moving or can't be movable