User thumbnail never loading.. what should I do?

I have this script for when a player joins the game, all you have to worry about is "PFP" I set its image value to the users thumbnail so it is preloaded for when a player wins an arena battle. Even with this, the users thumbnail in studio test mode is still the icon that shows no image is in the imagelabel, no errors

game.Players.PlayerAdded:Connect(function(plr)
    local fold = Instance.new("Folder",plr)
    fold.Name = "Stats"
    local battle = Instance.new("BoolValue",fold)
    battle.Name = "battle"
    battle.Value = false
    local kills = Instance.new("IntValue",fold)
    kills.Name = "kills"
    kills.Value = 0
    local pfp = Instance.new("ImageLabel",fold)
    pfp.Name = "PFP"
    local content, isReady = game.Players:GetUserThumbnailAsync(plr.UserId, Enum.ThumbnailType.HeadShot, Enum.ThumbnailSize.Size352x352)
    pfp.Image = content
end)