How do I make a succesful close button for my Pop-up Gui?

So I made a script where when a brick is touched a Gui opens:

local Part = script.Parent

Part.Touched:connect(function(HIT)
    local H = HIT.Parent:FindFirstChild("Humanoid")
    if H then
        local Player = game.Players:GetPlayerFromCharacter(HIT.Parent)
        Player.PlayerGui.NPC.ChatGuiOne.Frame.Visible = true
    end
end)

^ This isn't the problem, it works fine

This is kinda what my StarterGui looks like in the Explorer:

StarterGui
    NPC --Folder
        ChatGuiOne --ScreenGui
            Frame
                CloseButton --TextButton
                    LocalScript

This is what that LocalScript looks like:

script.Parent.MouseButton1Click:connect(function()
    script.Parent.Parent.Visible = false
end)

This didn't work so I thought maybe the problem was something to do with everything in StarterGui being cloned into PlayerGui, so I tried this:

script.Parent.MouseButton1Click:connect(function()
    game.Players.LocalPlayer.PlayerGui.NPC.ChatGuiOne.Frame.Visible = false
end)

Neither of them work. I hope I gave enough detail for someone to help me out. :-)