[GAMEPLAY] Permanent Oracle's Extract

So I was playing a ARAM match.Everything was fine, till I've noticed that I see Teemo's mushrooms when my Oracle's Extract was long gone and expired. I'm not sure how that happend.From what I saw on a replay I've bought an Oracle when I was dead, and just seconds after it expired I still was able to see the shrooms.This is very unfair for the opponents so Riot, please fix.

Here's a link to a video that I've recorded: https://youtu.be/hAlg2TtMWjM