Why is my data store system only temporarily storing my data?

I'm new to DataStoreSystems, but I watched this YouTube video on how to make one for my wins system, and even though the points go up, they don't permanently save. When I log back in, my wins just set back to 0. What did I do wrong?

local DataStoreService = game:GetService("DataStoreService")

local myDataStore = DataStoreService:GetDataStore("myDataStore")

game.Players.PlayerAdded:Connect(function(player) local leaderstats = Instance.new("Folder") leaderstats.Name = "leaderstats" leaderstats.Parent = player

local wins = Instance.new("IntValue")
wins.Name = "Wins"
wins.Parent = leaderstats

local data
local success, errormessage = pcall(function()
	data = myDataStore:GetAsync(player.UserId.."-Wins")
end)
	
if success then
	wins.Value = data
else
	print("Data not saved from success")
	warn(errormessage)
end

end)

game.Players.PlayerRemoving:Connect(function(player) local success, errormessage = pcall(function() myDataStore:SetAsync(player.UserId.."-Wins",player.leaderstats.Wins.Value) end)

if success then
	print("Data successfully saved")
else
	print("Data not saved")
	warn(errormessage)
end

end)

This save system prevents hackers and it autosaves.

local PlayerStatManager = {}

local DataStoreService = game:GetService("DataStoreService")
local playerData = DataStoreService:GetDataStore("PlayerData")

local sessionData = {}

local AUTOSAVE_INTERVAL = 60

function PlayerStatManager:ChangeStat(player, statName, value)
	local playerUserId = "Player_" .. player.UserId
	assert(typeof(sessionData[playerUserId[statName]) == typeof(value), "ChangeStat error: types do not match"
	if typeof(sessionData[playerUserId][statName]) == "number" then
		sessionData[playerUserId][statName] = sessionData[playerUserId][statName] + value
	else
		sessionData[playerUserId][statName] = value
	end
end

local function setupPlayerData(player)
	local playerUserId = "Player_" .. player.UserId
	local success, data = pcall(function()
		return playerData:GetAsync(playerUserId)
	end)
	if success then
		if data then
			sessionData[playerUserId] = data
		else
			sessionData[playerUserId] = {Points=0, Experience=0}
		end
	end
	local data = playerData:GetAsync(playerUserId)
	if data then
		sessionData[playerUserId] = data
		else
			sessionData[playerUserId] = {Points=0, Experience=0}
	    end
	else
		warn("Cannot access data stor for player!")
	end
end

local function savePlayerData(playerUserId)
	if sessionData[playerUserId] then
		local tries = 0
		local success
		repeat
			tries = tries + 1
			success = pcall(function()
				playerData:SetAsync(playerUserId, sessionData[playerUserId])
			end)
			if not success then wait(1) end
		until tries == 3 or success
		local success, err = pcall(function()
		    playerData:SetAsync(playerUserId, sessionData[playerUserId])
		end)
		if not success then
			warn("Cannot save data for player!")
		end
	end
end)

local function saveOnExit(player)
	local playerUserId = "Player_" .. player.UserId
	savePlayerData(playerUserId)
end

local function autoSave()
	while wait(AUTOSAVE_INTERVAL) do
		for playerUserId, data in pairs(sessionData) do
			savePlayerData(playerUserId)
		end
	end
end

spawn(autoSave)

game.Players.PlayerAdded:Connect(setupPlayerData)

game.Players.PlayerRemoving:Connect(saveOnExit)

return PlayerStatManager

Although, This is the standard script from ROBLOX script thing idk what it is called but it's from ROBLOX.

Line 12 is still one big line, the answer bar did not have enough room.