Permissions in regards of privacy can change from time to time at the notification of Facebook's Privacy team. To control your permissions when signing up or re-adding a game application like ours to your Facebook profile, please click the following link for more information.
How do I control my permissions when I sign up for an app or game?
From the link above, you will be able to learn how to manage the app's privacy settings. One of the settings in here should be the Friend List, for example. If this option is visible, it should have a blue-white check mark and your in-game Friend List should be available for gifting and/or inviting. If there is no Friend List option, please check your personal privacy settings here: