Kennen [BUG] Electrical Surge - Lightning Rush BUG [GAMEPLAY]

When I use Electrical Surge on marked targets (minions and champions marked before with Lighting Rush) Electircal Surga do nothing on some target (usually 2-3 out of 6) even if they definitely marked before with Lighting Rush!!!! In the last 2 weeks (or so) this bug come up very often. This time, doing a Lightning Rush -> Electrical Surge -> Slicing Maelstrom combo is so so unpredictable... Kennen is almost usless now. Please check it and fix it!