[Gameplay] Zilean passive bug

So after the latest patch, about 5 times so far in about every 3rd game or so I've played, I've used the passive on an ally and instead it uses my E skill on myself. I have no idea how to reproduce this and it seems to happen randomly. I'm certain I'm not just pressing shit on my keyboard, only thing I do is just click on their yellow circle with my mouse, I get a small lag and then I hear my E sound and it's on cooldown.