The Dark Seal *Bugged*

The Dark Seal item is bugged, or at the very least it was for me, It says that it gives +3 AP per 1 Glory, I was playing as Kass and picked it up as staring item just to see how it would go, I ended up obtaining 5 Glory that game and the item gave 0 bonus AP when i was supposed to be getting +15 if im correct. I tried to get a screen shot of it but Print Screen gave me a black image instead, RIP. So i was just wondering if this is a confirmed bug or if it was just a one time thing and if anyone else has noticed anything else like it?