Why isn't my onPlayerLeft function saving Cash value?

I am able to get my player Cash value to load. When I spend money in game the leaderstats change how they should. When I leave and re-join, my player's Cash value is back to the starting_cash value. I am also getting an error saying "Argument 2 missing or nil". Can someone give any idea how to make the cash value actually save?

local Players = game:GetService("Players")
local CashDataStore = game:GetService("DataStoreService"):GetDataStore("Cash") 

local STARTING_CASH = 100

local function onPlayerAdded(player)
    local playerKey = "Player_" .. player.UserId

    print("User ".. player.UserId.. " Joined")

    local leaderstats = Instance.new("IntValue")
    leaderstats.Name = "leaderstats"

    local Cash = Instance.new("IntValue", leaderstats)
    Cash.Name = "Cash"

    local myCash
    local success, err = pcall(function()
        myCash = CashDataStore:GetAsync(playerKey) or STARTING_CASH
    end)
    if success then
        Cash.Value = myCash
        print("loading "..myCash)
    else
        -- Failed to retrieve data
    end

    leaderstats.Parent = player
end

for _, player in pairs(Players:GetPlayers()) do
    onPlayerAdded(player)
end
Players.PlayerAdded:Connect(onPlayerAdded)

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local function onPlayerLeft(player)
    local playerKey = "Player_"..player.UserId

    local savedCash = player.leaderstats.Cash.Value
    savedCash = CashDataStore:UpdateAsync(playerKey)
    print("User "..player.UserId.." disconnected")
    print("User has "..savedCash.." in the bank")   

end
Players.PlayerRemoving:Connect(onPlayerLeft)