[SOLVED] What's wrong with ProcessReceipt? [closed]

I figured out another method to do this.

I'm trying to make a donate with Developer Products for my new game, and am refraining from using Free Models, as let's face it. A lot of them are bad quality and or have a virus in them that lags the game.

Every time I join, an online server (I'm using ROBLOX's Remote Error Monitoring System) it throws this error: ProcessReceipt is not a valid member of MarketplaceService.

But I've scripted it in a similar way to what's on the wiki, unless that's wrong.

Here's the script.

I've cut out the purchase part of the script, but if needed, I will add it.

ProductID       = 19253009
ProductPrice    = 5
CurrencyType    = "TIX"

DS              = game:GetService("DataStoreService"):GetDataStore("Places")
MS              = game:GetService("MarketplaceService")

--ERROR DOWN HERE.
MS.ProcessReceipt = function(Info)
DS:IncrementAsync(CurrencyType.."_Raised",Info.CurrencySpent)
DS:OnUpdate(CurrencyType.."_Raised",PrintOut)
script.Parent.SurfaceGui.Raised.ROBUX.Text = CurrencyType.." "..Raised
script.Parent.Purchased:play()
script.Parent.Jingle:play()
wait(5)
for i = .5,0,-.05 do
script.Parent.Jingle.Volume = i
wait()
end
script.Parent.Jingle:stop()
return Enum.ProductPurchaseDecision.PurchaseGranted 
end

Any ideas to what might be wrong?