DataStore not working im not getting any error message when i join it doesn't loads?

Improvements

Use WaitForChild() to make sure an instance exists before using it

Use GetService() for ReplicatedStorage and Players

Issues

When Loading the Data, you are using SetAsync(key, value) when you should be using GetAsync(key)

Revised Server Script

local DataStoreService = game:GetService("DataStoreService")
local myDataStore = DataStoreService:GetDataStore("myDataStore")

local repst = game:GetService("ReplicatedStorage")

game:GetService("Players").PlayerAdded:Connect(function(plr)
	local pdata = repst:WaitForChild(plr.Name.."Stats")
	local success, errormessage = pcall(function()
		myDataStore:GetAsync(plr.UserId)
	end)
	
	if success then
		local data = myDataStore:GetAsync(plr.UserId)
		if data then
			print("Data Loaded!")
			for index, value in pairs(pdata:GetChildren()) do
				value.Value = data[value.Name]
			end
		else
			print("No Data")
		end
	else
		warn(errormessage)
		print("Data didn't Load Successfully!")
	end
end)

game:GetService("Players").PlayerRemoving:Connect(function(plr)
	local pdata = repst:WaitForChild(plr.Name.."Stats")	
	local data = {}
	for index, value in pairs(pdata:GetChildren()) do
		data[value.Name] = value.Value
	end
	
	local success, errormessage = pcall(function()
		myDataStore:SetAsync(plr.UserId, data)
	end)
	
	if success then
		print("Data Successfully Saved!")
	else
		warn(errormessage)
		print("There was an error while saving game!")
	end
end)