Whats the problem with my script?

game.Players.PlayerAdded:connect(function(nP) -- connect event to anonymous function
nP.CharacterAdded:connect(function(nC) -- connect event to anonymous function
sg = Instance.new("ScreenGui", nP.PlayerGui) -- create the screengui
sg.Name = "Welcome" -- set its name
fr = Instance.new("Frame", sg) -- create the frame inside the ScreenGui
fr.Size = UDim2.new(0, 150, 0, 30) -- set its size
fr.Position = UDim2.new(0, 0, 0.5, -15) -- center the frame
fr.Style = "RobloxRound"
tb = Instance.new("TextButton", fr) -- create a textbutton, put it in frame
tb.Size = UDim2.new(1, 0, 1, 0)
tb.Style = "RobloxButtonDefault"
tb.TextColor3 = Color3.new(1, 1, 1)
tb.Text = "Join Game"
tb.MouseButton1Click:connect(function(Plr)
    local Humanoid = clicker and clicker.Parent and clicker.Parent:FindFirstChild("Humanoid")
    if Humanoid then 
        Humanoid.Torso.CFrame = CFrame.new (Vector3.new(-683, 43.201, -81))
    end
end)
end)
end)

This is a script that teleports a player to certain place when he clicks the Gui