Why has this script from the wiki stopped working after some time, is this an issue with roblox?

Greetings,

I used a script directly from the wiki to handle dev product purchases and it worked fine at first but now after a few hours it stops at line 62 and fires a warning instead.

https://developer.roblox.com/en-us/articles/Developer-Products-In-Game-Purchases

My question is: Is this an issue on my end, like I messed something up (even tho i didn't edit the script at all, or is this a temporary problem with roblox services? Because i get the prompt i press yes and it says purchase completed but it gives me the error in output and doesn't give me the item

For your convenience i'll post the script in question here (the script stops at line 31 in this post)

 
-- The core 'ProcessReceipt' callback function
local function processReceipt(receiptInfo)
 
	-- Determine if the product was already granted by checking the data store  
	local playerProductKey = receiptInfo.PlayerId .. "_" .. receiptInfo.PurchaseId
	local purchased = false
	local success, errorMessage = pcall(function()
		purchased = purchaseHistoryStore:GetAsync(playerProductKey)
	end)
	-- If purchase was recorded, the product was already granted
	if success and purchased then
		return Enum.ProductPurchaseDecision.PurchaseGranted
	elseif not success then
		error("Data store error:" .. errorMessage)
	end
 
	-- Find the player who made the purchase in the server
	local player = Players:GetPlayerByUserId(receiptInfo.PlayerId)
	if not player then
		-- The player probably left the game
		-- If they come back, the callback will be called again
		return Enum.ProductPurchaseDecision.NotProcessedYet
	end
	
	-- Look up handler function from 'productFunctions' table above
	local handler = productFunctions[receiptInfo.ProductId]
 
	-- Call the handler function and catch any errors
	local success, result = pcall(handler, receiptInfo, player)
	if not success or not result then
		warn("Error occurred while processing a product purchase")
		print("\nProductId:", receiptInfo.ProductId)
		print("\nPlayer:", player)
		return Enum.ProductPurchaseDecision.NotProcessedYet
	end
 
	-- Record transaction in data store so it isn't granted again
	local success, errorMessage = pcall(function()
		purchaseHistoryStore:SetAsync(playerProductKey, true)
	end)
	if not success then
		error("Cannot save purchase data: " .. errorMessage)
	end
 
	-- IMPORTANT: Tell Roblox that the game successfully handled the purchase
	return Enum.ProductPurchaseDecision.PurchaseGranted
end
 
-- Set the callback; this can only be done once by one script on the server! 
MarketplaceService.ProcessReceipt = processReceipt