This is an issue that’s been bothering me for some time. Several events (such as the current Faction Assault event) have a “new title” available as a reward. However, as you can see by the screenshots below, this reward is still listed as a “new title,” even if you already have that title unlocked! Take a look:
Is there any chance that you could indicate that a particular title or portrait has already been unlocked on the rewards page? An additional word next to it saying “(Owned)” would go a long way, I think, and would likely be very easy to add.