How come this script wont save even though it has 3 saving things?

local datastore = game:GetService("DataStoreService")
local ds1 = datastore:GetDataStore("NCSaveSystem")
local ds2 = datastore:GetDataStore("BoogieSaveSystem")
local ds3 = datastore:GetDataStore("RebirthSaveSystem")

game.Players.PlayerAdded:connect(function(plr)
 local folder = Instance.new("Folder", plr)
 folder.Name = "leaderstats"
 local NC = Instance.new("IntValue", folder)
 NC.Name = "NoseCoins"
 local boogers = Instance.new("IntValue", folder)
 boogers.Name = "Boogies"
 local Rebirths = Instance.new("IntValue", folder)
 Rebirths.Name = "Rebirths"
 
 NC.Value = ds1:GetAsync(plr.UserId) or 0
 ds1:SetAsync(plr.UserId, NC.Value)
	
 boogers.Value = ds2:GetAsync(plr.UserId) or 0
 ds2:SetAsync(plr.UserId, boogers.Value)
	
 Rebirths.Value = ds3:GetAsync(plr.UserId) or 0
 ds3:SetAsync(plr.UserId, Rebirths.Value)	
 
 NC.Changed:connect(function()
  ds1:SetAsync(plr.UserId, NC.Value)
 end)
 
 boogers.Changed:connect(function()
 ds2:SetAsync(plr.UserId, boogers.Value)
		
 Rebirths.Changed:connect(function()
 ds3:SetAsync(plr.UserId, Rebirths.Value)
 end)
 end)
end)

I have been trying to do an actual working save script for about 2 years now. HOW THE HELL DOES EVERYBODY GET THEIRS TO SAVE???!!!!!!

First question, why are you using 3 datastores? Also, you should be using NumberValues, not IntValues.

You also don't reference any of the DataStores in your script, you just save them as variables.

Here, let me fix your code.

local dss = game:GetService('DataStoreService')
local datastore = dss:GetDataStore('putsomethingrandomhere')

game.Players.PlayerAdded:Connect(function(player)

local leaderstats = Instance.new('Folder')
leaderstats.Name = 'leaderstats'
leaderstats.Parent = player

local nosecoins = Instance.new('NumberValue')
nosecoins.Name = 'Nose Coins'
nosecoins.Value = 0 or datastore:GetAsync(player.UserId)['Nose Coins']
nosecoins.Parent = leaderstats

local boogers = Instance.new('NumberValue')
boogers.Name = 'Boogies'
boogers.Value = 0 or datastore:GetAsync(player.UserId).Boogies
boogers.Parent = leaderstats

local rebirths = Instance.new('NumberValue')
rebirths.Name = 'Rebirths'
rebirths.Value = 0 or datastore:GetAsync(player.UserId).Rebirths
rebirths.Parent = leaderstats

game.Players.PlayerRemoving:Connect(function()
datastore:SetAsync(player.UserId, {

['NoseCoins'] = player.leaderstats['Nose Coins'].Value
['Boogies'] = player.leaderstats.Boogies.Value
['Rebirths'] = player.leaderstats.Rebirths.Value

})

That should work, LMK if there are any problems when you test it!