Inconsistencies with dev products?

So idk if this is a network problem or something but i have a very simple script that clones a folder from serverstorage to your players pets folder when you purchase a developer product, now the issue is that sometimes it works and sometimes it doesn't. Maybe its a loading issue with the entire game since there are alot of scripts? or is there some roblox issues?

local MarketPlaceService = game:GetService("MarketplaceService")
local DPID = 1178453273
local Players = game:GetService("Players")

MarketPlaceService.ProcessReceipt = function(ReceiptInfo)
	local Player = Players:GetPlayerByUserId(ReceiptInfo.PlayerId)	
	if Player then
		if ReceiptInfo.ProductId == DPID then
			local ServerStorage = game:GetService("ServerStorage")
			local RobuxPets = ServerStorage:WaitForChild("RobuxPets")
			local DemonicDominus = RobuxPets:WaitForChild("Demonic Dominus")
			local DemonicDominusClone = DemonicDominus:Clone()
			DemonicDominusClone.Parent = Player:WaitForChild("Pets")
			local PetID = DemonicDominusClone:FindFirstChild("PetID")
			local Rand = math.random(2,1000000)
			print(Rand)
			PetID.Value = Rand
			return Enum.ProductPurchaseDecision.PurchaseGranted
		end
	else
		return Enum.ProductPurchaseDecision.NotProcessedYet
	end
end