Why does DataStore not working?It was working like a month ago, but now it isn't working.

I wrote a Datastore script like a month ago, and it was working back then, but now its not working. Please help me, thanks. Script:

local DataStoreService = game:GetService("DataStoreService")
local myDataStore = DataStoreService:GetDataStore("myDataStore")

game.Players.PlayerAdded:Connect(function(player)

    local DATAS = Instance.new("Folder")
    DATAS.Name = "leaderstats"
    DATAS.Parent = player

    local Level = Instance.new("IntValue")
    Level.Name = "level"
    Level.Parent = DATAS

    local currexp = Instance.new("IntValue")
    currexp.Name = "currentexp"
    currexp.Parent = DATAS

    local exptolvlup = Instance.new("IntValue")
    exptolvlup.Name = "exptolevelup"
    exptolvlup.Parent = DATAS

    local Beri = Instance.new("IntValue")
    Beri.Name = "Beri"
    Beri.Parent = DATAS

    local playerUserId = "player_"..player.UserId

    --Adat betöltése
    local data
    local success, errormessage = pcall(function()
        data = myDataStore:GetAsync(playerUserId)
    end)


    if success then
        if data then
            Beri.Value = data.Beri
            exptolvlup.Value = data.exptolvlup
            currexp.Value = data.currexp
            Level.Value = data.Value
        end
    end
end)

game.Players.PlayerRemoving:Connect(function(player)
    local playerUserId = "player"..player.UserId
    local data = {
        Beri = player.leaderstats.Beri.Value;
        Level = player.leaderstats.level.Value;
        currexp = player.leaderstats.currentexp.Value;
        exptolvlup = player.leaderstats.exptolevelup.Value
    }
    local success, errormessage = pcall(function()
        myDataStore:SetAsync(playerUserId, data)
    end)
    if success then
        print("Data successfully saved!")
    else
        print("Error!")
        warn(errormessage)
    end
end)