Loading script that worked suddenly doesnt?

I have a loading script thats been in my game and suddenly it stopped working

co = game:GetService("ContentProvider")
plr = game.Players.LocalPlayer
gui = plr.PlayerGui.Loading_Screen
blur = Instance.new("BlurEffect", game.Lighting)
blur.Size = 20
gui.Loading_Frame.Visible = true
game.StarterGui:SetCoreGuiEnabled(Enum.CoreGuiType.All, false)
assets = game:GetDescendants()
for i = 1, #assets do
    local percent = i/#assets
    local int = math.floor(i/#assets * 100)
    local asset = assets[i]
    co:PreloadAsync({asset})
    gui.Loading_Frame.Slider.Size = UDim2.new(percent, 0, 1, 0)
    gui.Loading_Frame.Percent_Display.Text = int.."%"
end
repeat wait() until plr.Character
wait(1)
gui.Loading_Frame:TweenPosition(UDim2.new(.3, 0, 1.1, 0), "In", "Linear", .3)
for i = 1, blur.Size do
    blur.Size = blur.Size - 1
    wait(.1)
end
blur:Destroy()
gui.Parent:Destroy()
game.StarterGui:SetCoreGuiEnabled(Enum.CoreGuiType.Chat, true)
game.StarterGui:SetCoreGuiEnabled(Enum.CoreGuiType.PlayerList, true)
game.StarterGui:SetCoreGuiEnabled(Enum.CoreGuiType.Backpack, true)

ive tried uninstalling and reinstalling roblox, completely rescripting it and everything, plz help error message: 12:29:37.912 - BackgroundImage is not a valid member of Frame 12:29:37.916 - Stack Begin 12:29:37.918 - Script 'Players.Vetrodex.PlayerScripts.ChatScript.ChatMain.ChannelsTab', Line 212 - function AnimGuiObjects 12:29:37.919 - Script 'Players.Vetrodex.PlayerScripts.ChatScript.ChatMain.ChannelsTab', Line 262 - function Update 12:29:37.920 - Script 'Players.Vetrodex.PlayerScripts.ChatScript.ChatMain.ChannelsBar', Line 352 - function Update 12:29:37.920 - Script 'Players.Vetrodex.PlayerScripts.ChatScript.ChatMain.ChatWindow', Line 650 - function Update 12:29:37.921 - Script 'Players.Vetrodex.PlayerScripts.ChatScript.ChatMain', Line 192 12:29:37.922 - Stack End