I'll admit I was a little confused on what the objective was. On my end, all the balls were the same color, and I'm guessing that getting them all into green wasn't the main objective. Chances are this was just a Unity error. Other than that, I would make sure the balls always move with the paddles, so that they don't go through the paddles when they are suddenly pushed up. Other than that, controlling the panels felt smooth, and the game was easy to look at.