Troubles with Orianna

There was once a time where I was a great Orianna player. I could coordinate with my team and set up for the best team fights. I had scarcely lost a game.
After a while, I decided to try other champs. I learned Lux, Lissandra, Lucian, Ezreal, Thresh, and Rumble. All mage-esque. I got quite good with all of them. However, I longed for my roots, and I decided to play some more Orianna.

And for some reason, I just utterly suck.

I still remember the plays and moves. I can definitely farm and lane against my opponents (for the most part). My builds have changed, adapted, but overall, I know how to build her. And yet for some inexplicable reason, I can't win anymore.

Checking my match history, my last win with her was June 3rd. In my last ten matches with her, I've lost nine of them.

That's pathetic.

So, what's changed? Is it just I've played too much of other champs? Is it that people nowadays don't know how to play with her? What's going on?