Why is my data saving script failing to overwrite data?

I have this saving script and I just learned that it is failing to overwrite data. It does it perfectly the first save, but it won't overwrite data.

local Players = game:GetService("Players")
local DataStoreService = game:GetService("DataStoreService")
local DataStore = DataStoreService:GetDataStore("-xBuckDatax-")

-- Making the saving inside a function
local function Save(player)
    local key = player.UserId
	local plr = workspace:WaitForChild(player.Name)

    local save = {
        ["SeerBux"] = player.leaderstats["SeerBux"].Value,
		["SpdWaitTime"] = player.WaitTime.WaitTimeSpd.Value,
		["StrWaitTime"] = player.WaitTime.WaitTimeStr.Value,
		["walkSpeed"] = plr:WaitForChild('Humanoid').WalkSpeed,
		["customize"] = player.Customize.Value,
		["Exp"] = player.ExperiencePts.Value,
		["level"] = player.leaderstats.Level.Value,
		["SpdCheck"] = player.SpdCheck.Value,
		['energy'] = player.EnergyCount.Value,
		['enbool'] = player.EnergyBool.Value
    }

    --saves their key and money to the data store
    local success, err = pcall(function()
        DataStore:SetAsync(key, save)
    end)

    if not success then
        warn("Failed to over-write data"..tostring(err))
        return
    end
end

-- The function to load a players data
local function Load(player)
    -- saves the player Id as key
    local key = player.UserId
	local plr = workspace:WaitForChild(player.Name)

    local moneyAlready

    local success, err = pcall(function()
        moneyAlready = DataStore:GetAsync(key)
    end)

    if not success then
        warn("Failed to read data"..tostring(err))
        return
    end

    if moneyAlready then
        player.leaderstats.SeerBux.Value = moneyAlready.SeerBux
		player.WaitTime.WaitTimeSpd.Value = moneyAlready.SpdWaitTime
		player.WaitTime.WaitTimeStr.Value = moneyAlready.StrWaitTime
		plr:WaitForChild('Humanoid').WalkSpeed = moneyAlready.walkSpeed
		player.Customize.Value = moneyAlready.customize
		player.leaderstats.ExperiencePts.Value = moneyAlready.ExperiencePts
		player.leaderstats.Level.Value = moneyAlready.Level
		player.SpdCheck.Value = moneyAlready.SpdCheck
		player.EnergyCount.Value = moneyAlready.energy
		player.EnergyBool.Value = moneyAlready.enbool
		
    else
        Save(player)
    end
end

Players.PlayerAdded:Connect(Load)
Players.PlayerRemoving:Connect(Save)