Electronic Window didn't want to move.

Two days ago I was driving my buddies back to their homes. We go to the same college so we all carpool in my Prius since it's the best on gas. On the way back we passed by a McDonalds drive through to get my buddy a soda He put his window down, the back left window. ONce we started moving it wouldn't move up. I turned on the AC and then the window moved fine. I tested all the other windows and they worked during both conditions.

I started moving again and tried the window thing again, and again it wouldn't work properly. After some time it started working again.

I have no idea what caused this or what could have caused this.

Has anyone had this problem before? What might it be?