Gui destroy() onTouch?

I have a brick that when touched a Gui will pop up on your screen. The only problem is, I can't figure out how to detect when the player is not on the brick, and have the script then destroy the Gui. I have tried script.destroy() but still nothing. Can someone please help me out with this?

local Gui = game.Lighting.World1 --Replace this with the location of your GUI

function GiveGui(Player)
if Player.PlayerGui:FindFirstChild(Gui.Name)~=nil then return end
Gui:Clone().Parent=Player.PlayerGui
end

script.Parent.Touched:connect(function(hit)

local Player=game.Players:GetPlayerFromCharacter(hit.Parent)
if Player==nil then return end
GiveGui(Player)

end)

I see you know the Touched event, but did you know that there is a TouchEnded event? It fires whenever a part stops touching another part.

Just check to make sure that this script is in a regular Script, as opposed to a LocalScript or a ModuleScript.

Check this out:

local Gui = game.Lighting.World1

function GiveGui(Player)
	if not Player.PlayerGui:FindFirstChild(Gui.Name) then
		Gui:Clone().Parent=Player.PlayerGui
	end
end

function RemoveGui(Player) --A function to remove the GUI.
	for i,v in pairs(Player.PlayerGui:GetChildren()) do
		if v.Name == Gui.Name then
			v:Destroy()
		end
	end
end

script.Parent.Touched:connect(function(hit)
	local Player=game.Players:GetPlayerFromCharacter(hit.Parent)
	if Player then
		GiveGui(Player)
	end
end)

script.Parent.TouchEnded:connect(function(hit) --This fires when the part stops touching the Brick.
	local Player=game.Players:GetPlayerFromCharacter(hit.Parent)
	if Player then
		RemoveGui(Player)
	end
end)

:)