why doesnt my local script doesnt work in the game?? (open/close gui)

The question says it all, I created a successful script thanks to a few people who helped me previously, and they work in test mode. But not in the actual game

local Text = game.Players.LocalPlayer.PlayerGui.ScreenGui.TextLabel
script.Parent.MouseButton1Click:connect (function()

    if Text.Visible == false then Text.Visible = true else
    Text.Visible = false
end

end)