Why won't this simple script work?

What is wrong with the following that even when someone else that is not me sit's on the seat they still get the gui?

gui = game.Lighting.Control 

function getGUI(u)
print("hit")
local h = u.Parent:FindFirstChild("Humanoid")
if h ~= nil then
print("human")
local user = game.Players:GetPlayerFromCharacter(u.Parent)
local gtest = user.PlayerGui:FindFirstChild("ScreenGui")
print(u.ClassName,u.Name) 
if user.Name == "DavidWhitmore" then
if gtest == nil then
local g = gui:Clone()
g.Parent = user.PlayerGui
else return end
print("Done")
end
end
end

script.Parent.Touched:connect(getGUI)