Datastore script either doesnt save or doesnt load, dont know whats wrong with it?

When you're loading the data you're not actually using it, you're just checking if its there....

local datastoreservice = game:GetService("DataStoreService")
local datastorage = datastoreservice:GetDataStore("datastorage")
print("Variables loaded")

local currentSession = {}

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

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

    print("Leaderstats created")

    local data
    local success, errormessage = pcall(function()
	return data = datastorage:GetAsync(player.UserId) --added "return"
    end)
    print("Data load happened")

    if success then --cool, its there, so what?
        print("Data loaded") 
---Here
	if data then --if theres data, act on it
		player.leaderstat.Nights.Value = data
	else
		--setup some default data (for first time-players) etc.
	end
--To here
    else
        warn("Error happened while loading data: "..errormessage)
    end
end

local function Save(player)
    for i, player in pairs(game:GetService("Players"):GetPlayers()) do
        local success, errormessage = pcall(function()
            datastorage:SetAsync(player.UserId, player.leaderstats.Nights.Value)        
        end)    

        if success then
            print("Data saved")
        else
            warn("Error happened while saving data: "..errormessage)
        end     
    end
end

game.Players.PlayerAdded:Connect(Load)
game:BindToClose(Save)

I think this should help? if its still not working let me know and I'll have another look... I'm pretty new to this too so I've probs missed something haha This guide is pretty good!