How can you save the value of any Value?

Alright so it may sound a bit repetitive, but try to understand. Specifically a boolean value, I need to save the value of the Boolean Value itself. Since I know you cant save the Boolean Value itself, I know you can save the value of it. Anyway, I tried to do it here, but It doesn't work. Can anyone please explain why?

So, first I used SetAsync() which didn't work, so then I try UpdatedAsync() which doesn't work either. All I need to do is just save the value of the BoolValue so which one should I use? P.S. Everyone receives a bool value inside the folder named PlayerValues that is cloned to every player.

Every time I join the game it says the value is saved, but when I rejoin it says that it is false, turns true, and saves it again.

game.Players.PlayerAdded:Connect(function(player)
	local ValueDataStore = game:GetService("DataStoreService"):GetDataStore("SaveValueDataStore")
	local ValueNeedSaving = player:WaitForChild("PlayerValues",1):FindFirstChild("ValueNeedSaving")
	local valuekey = 0
	if ValueNeedSaving.Value == true then
		print("This value is already true!")
	else
		--SAVE TABLE PART--
		ValueNeedSaving.Value = true
		ValueDataStore:UpdateAsync(AlreadyGivenValue.Value, function()
			return AlreadyGivenValue.Value or 0
		end)
		print("The Value was saved and it will stay true!")
end)