This playerlist script and GUIs I made aren't working. Any ideas why?

wait()
local Frame = script.Parent
local Template = Frame.Players
local Script = script
local Players = game:GetService("Players")
local function UpdateLeaderboard(Player)

    local Count = 0
    for i,v in pairs(Players:GetChildren()) do
        Count = Count + 1
        local Slot = Template:Clone()
        Slot.Parent = Frame
        local SlotY = 0.078 * Count
        Slot:TweenPosition(UDim2.new(-0.254,0,SlotY,0), "Out", "Linear", 0)
        Slot.Name = Player.Name
        Slot.Text = Slot.Name
    end
end

game.Players.PlayerAdded:Connect(function(Player)
    UpdateLeaderboard(Player)
end)

game.Players.PlayerRemoving:Connect(function(Player)
    UpdateLeaderboard(Player)
end)

How its setup: https://gyazo.com/0d3f65c7a7d320a744f0ec0be433747e