help !! there something wrong with my script . The script won't save data when i left the game ?

You cannot set it to GetAsync when player is removing, as it won't save data. Instead use SetAsync to save at when player is removing

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

game.Players.PlayerAdded:Connect(function(player)
    local cash = Instance.new("IntValue")
    cash.Name = "Kronos"
    cash.Parent = player

    local data
    local success, errormessage = pcall(function()
        data = myDataStore:GetAsnyc(player.UserId.."-cash")
    end)

    if success then
        cash.Value = data
    else
        print("Failed to save data")
        warn(errormessage)
    end
end)

game.Players.PlayerRemoving:Connect(function(player)
    local success, errormessage = pcall(function()
        myDataStore:SetAsync(player.UserId.."-cash", player.Cash.Vaule)
    end)

    if success then
        print("Data saved")
    else
        print("Failed to save data")
        warn(errormessage)
    end
end)

This should work