Touched event to open/close GUI not working in game?

game.Workspace["Shop"]:WaitForChild("buy").Touched:connect(function(player)
    if player.Parent:FindFirstChild("Humanoid") then
        local playername = game:GetService("Players"):FindFirstChild(player.Parent.Name)
        if playername.PlayerGui:FindFirstChild("shop").Frame.Visible == false and playername.PlayerGui:FindFirstChild("AnimShop").Frame.Visible == false then
            playername.PlayerGui:FindFirstChild("shop").Frame.Visible = true
        end
    end
end)

This script is supposed to make the gui visible when a player touches a brick called "buy". It works perfectly in studio but not in game. How can I fix this?