title: Integrate facebook credits in facebook apps
body: <p>I want to Integrate facebook credits in my fb apps. I downloaded sample code from referral site but that is not working. </p>
  
  <p>My app link is <code>apps.facebook.com/football_leagues</code> and from <code>fan$</code> link when you click at redeem , a popup window opens for credits. But I get an error message: </p>
  
  <blockquote>
    <p>There was an error making your Facebook Credits purchase.
    Order::update_order called with invalid state transition:3 -> 0</p>
  </blockquote>