Developer Products. Currency Type not working?

I've been trying to find an answer to this all day. I'm trying to find if the Player has purchased in either Robux or Tix, using the new developer products feature.

if receiptInfo.CurrencyType == Enum.CurrencyType.Robux then

This line wont work, I have no idea why. Help appreciated im growing very tired of this one line.

EDIT Heres the full code if you see no problem with the line.

local MarketplaceService = Game:GetService("MarketplaceService")
local ds = game:GetService("DataStoreService"):GetDataStore("PurchaseHistory")

MarketplaceService.ProcessReceipt = function(receiptInfo)
	hi = Instance.new("Hint")
	hi.Parent = game.Workspace
	hi.Text = receiptInfo.PlayerId .. " has donated with "..receiptInfo.CurrencyType..""
	wait(2)
	hi:destroy()	
	if receiptInfo.CurrencyType == Enum.CurrencyType.Robux then
		script.Parent.Parent.Pos1.Transparency = 1
		script.Parent.Parent.Tix.Value = script.Parent.Parent.Tix.Value + 1
	elseif receiptInfo.CurrencyType == Enum.CurrencyType.Tix then
		script.Parent.Parent.Pos2.Transparency = 1
		script.Parent.Parent.Robux.Value = script.Parent.Parent.Robux.Value + 1
	else script.Parent.Parent.Main.Transparency = 0.5
	end
	return Enum.ProductPurchaseDecision.PurchaseGranted 

end

Well, the best wiki page I can find about this would be this. My knowledge on Enum's are very limited, but according to the code, it reads in numbers.

And after more research, I found that the Enum's are put into numbers. Don't know if it helps you or not, but perhaps try something like;

if receiptInfo.CurrencyType == Enum.CurrencyType.2 then

Or maybe perhaps;

if receiptInfo.CurrencyType == 2 then

This is all based on my readings of;

If, for example, the user account ROBLOX were to buy a developer product with an ID of 1234, with Robux, the TextLabel would change to be equal to "1 just bought 1234 with 2"