The Dark Seal counter's do not do as intended.

I have been playing MANY games with the item "The Dark Seal" as my laying item to start off with as LeBlanc. As I proceed to get my kill's/assists to collect my counters, I hover over the item and it says that i'm receiving 15AP (+0) when I have counters on them. I was sitting at it's max counters (10) which should be an increase of 30AP yet I am still only receiving a boost of the initial 15AP and no addition of the 30AP for a total of 45AP I should be getting from the item. If I am able to get screen shots or whatnot I will try to post them on here too.