How do you make leaderstats that will save for the player?

local dss = game:GetService("DataStoreService")
local data = dss:GetDataStore("Data")

game.Players.PlayerAdded:Connect(function(plr)
	
	local folder = Instance.new("Folder", plr)
	folder.Name = "leaderstats"
	
	local coins = Instance.new("IntValue", folder)
	coins.Name = "Coins"
	print("Sucess!")
	
	local pd 
	
	local success, errormessage = pcall(function()
	pd = data:GetAsync(plr.UserId.."-coins")
	end)
		if success then
			coins.Value = pd	
	else
		print("There was an error")
				warn(errormessage)
		end
end)

game.Players.PlayerRemoving:Connect(function(plr)
	
       local success, errormessage = pcall(function()
	data:SetAsync(plr.UserId.."-coins", plr.leaderstats.cash.Value)
	end)
		
		if success then
			print("Player's Data has been saved!")
	else
			print("Player's Data has not been saved!")
			warn(errormessage)
		end
end)

but it printed "Players data hasn't been saved!"

This is super simple to do just type this and im assuming you know how to make a basic leaderboard.

script

local datastore = game:GetService("DataStoreService")
local ds1 = datastore:GetDataStore("CoinSaveSystem")

game.Players.PlayerAdded:connect(function(plr)
 local leaderstats = Instance.new("Folder", plr)
 leaderstats.Name = "leaderstats"
 local Coin = Instance.new("IntValue", leaderstats)
 Coin.Name = "Coins"

 
 Coin.Value = ds1:GetAsync(plr.UserId) or 0
 ds1:SetAsync(plr.UserId, Coin.Value)
 
 
 Coin.Changed:connect(function()
  ds1:SetAsync(plr.UserId, Coin.Value)
 end)
 
 Coin.Changed:connect(function()
	print("success")
 end)
end)

Then Enable Studio Access to API Services: and turn it on. When you turn it on it should show a check mark! in the box or if you go to studio and open game setting and click On on API service.