TweenPosition works on Studio testing but not game server, why?

Hello.

I've been trying to get my Trello enabled music player to work, but everything I tried does not work. The entire code works perfectly fine during normal studio testing. But on a game server, :TweenPosition does not work. However, the music still plays.

Here's my code:

local Background = script.Parent.Background

function create(class, parent)
    local cre = LoadLibrary("RbxUtility").Create
    return function(properties)
        local inst = cre(class)(properties)
        inst.Parent = parent

        return inst
    end
end

local function shuffleTable(t)
    math.randomseed(tick())
    assert(t, "shuffleTable() expected a table, got nil")
    local iterations = #t
    local j
    for i = iterations, 2, -1 do
        j = math.random(i)
        t[i], t[j] = t[j], t[i]
    end
end

local Songs = {

}

local SongNum = 0

local http = game:GetService("HttpService")
local songs = http:JSONDecode(http:GetAsync("https://api.trello.com/1/lists/58fc97dd846a0a0b60d304e1/cards"))
for _, v in pairs(songs) do
    if v.name:match(":") ~= nil then
        local s, f = string.find(v.name, ":")
        table.insert(Songs, string.sub(v.name, f + 1))
        game:GetService("ContentProvider"):Preload("rbxassetid://" .. string.sub(v.name, f + 1))
        print(Songs[#Songs])
    end
end

shuffleTable(Songs)

while wait() do
    SongNum = SongNum + 1
    if SongNum > #Songs then
        SongNum = 1
    end
    Background:TweenPosition(UDim2.new(0.5, -140, 0, 10), "Out", "Back", 0.5)
    Background.CurrentSong.Text = game:GetService("MarketplaceService"):GetProductInfo(Songs[SongNum]).Name
    game.ReplicatedStorage.Music.Value = game:GetService('MarketplaceService'):GetProductInfo(Songs[SongNum]).Name
    wait(5)
    Background:TweenPosition(UDim2.new(0.5, -140, -0.5, 10), "Out", "Back", 0.5)
    local Song = "rbxassetid://" .. Songs[SongNum]
    create("Sound", script.Parent.Parent.Parent) {
        Volume = 0.4;
        SoundId = Song;
        Name = "Music";
    }
    local Sound = script.Parent.Parent.Parent:FindFirstChild("Music")
    Sound:Play()
    wait(120)
    Sound:Stop()
    wait()
    Sound:Destroy()
end