Answers

Every call that changes data gives back the same three things:

local Ok, Result, Info = Session:Commit(Op)

• Ok is true if the change went through, and false if it didn't.
• Result: when Ok is false, this is the reason, a short string like "Refused". When Ok is true, it's something useful for that call, like the new data for Commit.
• Info has extra details when Ok is false. You'll mostly use it for "Unresolved", below.

There are 15 reasons, and each one means the same thing on every call. Compare with Ledger.Reason, so a typo shows up in Studio instead of silently never matching:

if Result == Ledger.Reason.Refused then

A full example

Here's the rare shop from Players, now handling its answers:

local function OnBuyRare(Player: Player)
	local Session = PlayerStore:Get(Player)
	if not Session then
		return -- still loading
	end

	local Ok, Result, Info = Session:Commit({ Kind = "BuyItem", Item = RARE_ITEM, Price = RARE_PRICE })
	if Ok then
		print(Player.Name, "bought the dragon")
		return
	end

	if Result == Ledger.Reason.Refused then
		print(Player.Name, "can't afford the dragon")
		return
	end

	if Result == Ledger.Reason.Unresolved and Info and Info.Outcome then
		print(Player.Name, "'s purchase is still saving")

		local Saved, Why = Info.Outcome:Wait()
		if not Saved then
			print(Player.Name, "'s purchase didn't go through:", Why)
			return
		end

		print(Player.Name, "bought the dragon")
		return
	end

	warn(Player.Name, "couldn't buy the dragon:", Result)
end

Most of your code only needs to handle a few reasons. Anything else is rare, so a warn is enough.

The ones you'll see

Unresolved

Unresolved doesn't mean it failed. It means Ledger doesn't know yet, and it keeps sending the change until it finds out. Don't send it again yourself, or the player could get it twice.

If you want to know how it ended, wait on Info.Outcome:

	if Result == Ledger.Reason.Unresolved and Info and Info.Outcome then
		print(Player.Name, "'s purchase is still saving")

		local Saved, Why = Info.Outcome:Wait()
		if not Saved then
			print(Player.Name, "'s purchase didn't go through:", Why)
			return
		end

		print(Player.Name, "bought the dragon")
		return
	end

Outcome:Wait() gives back true once it's saved, or false and a reason if it didn't go through. It yields, so it's fine inside a remote handler like this one, but don't call it anywhere that has to answer straight away.

Apply never answers Unresolved: it only queues the change, and the next save takes care of it.

In a long DataStore outage, a few minutes or more, an Unresolved change can be lost. For things that must never be lost, like Robux purchases, keep a record in the player's data. Once only shows how, and Purchases does it for Robux.

Telling the player why

Refused doesn't say which rule failed. If you want to show a message, check the same thing in your script before you send the change, like Bigger reducers does.

The rest

You won't see these unless you use the feature they belong to:

Next: Once only