Why Isn't My Script Working?

My script is supposed to add 100 money after buying a developers product but it isnt working. I got this script from roblox wiki

--LocalScript in StarterPack
-- setup local variables
local buyButton = game.Workspace.BuyButton.SurfaceGui.TextButton
local productId = 20805766
 
-- when player clicks on buy brick prompt him/her to buy a product
buyButton.MouseButton1Click:connect(function()
	game:GetService("MarketplaceService"):PromptProductPurchase(game.Players.LocalPlayer, productId)
end)
 
 
 
 
--Script in BuyButton part
-- setup local variables
local MarketplaceService = Game:GetService("MarketplaceService")
local ds = game:GetService("DataStoreService"):GetDataStore("PurchaseHistory")
local productId = 20805766
 
-- define function that will be called when purchase finished
MarketplaceService.ProcessReceipt = function(receiptInfo) 
 
	-- find the player based on the PlayerId in receiptInfo
	for i, player in ipairs(game.Players:GetChildren()) do
		if player.userId == receiptInfo.PlayerId then
 
 
			-- check which product was purchased
			if receiptInfo.ProductId == productId then
 
				-- handle purchase
				player.leaderstats.Money.Value = player.leaderstats.Money.Value + 100
			end
		end
	end	
 
	-- record the transaction in a Data Store
	local playerProductKey = "player_" .. receiptInfo.PlayerId .. "_purchase_" .. receiptInfo.PurchaseId
	ds:IncrementAsync(playerProductKey, 1)	
 
	-- tell ROBLOX that we have successfully handled the transaction
	return Enum.ProductPurchaseDecision.PurchaseGranted		
end

ipairs = inpairs