Wooglet's Witchcap AP Bonus bug

I was playing Hexakill on the twisted treeline when I looked at my AP when I was dead thinking "oh it will reset and the bonus will re-apply when I revive" However, as I revived, I watched it and when I looked at the bonus when I hovered over it, it said "25% bonus ability power (0)" and I was playing veigar , I was supposed to have over 800, but instead had 736. Not bad, but I died twice due to my lack of damage because of how much I had lost . It happened after I had purchased a fiendish codex while building a Morellonomicon . I lost a team fight and the game because of this bug, please fix this ... Also, as a side note, when I was level 20 a while back, this site said I was level 5 and I couldn't post any discussions.