OOO Partner?

[umpire99]

After a timeout, the team who is to throw in the ball is exiting their huddle and hustling to the spot for the throw-in. We have not had any trouble throughout the game with them taking too long. For some reason, my partner puts the ball on the floor and begins the five count. After a later timeout, the same team is ready to throw in the ball and I am ready to hand it to them when I see my partner with his back to the court talking to somebody in the front row. I blow my whistle and administer the throw-in. My partner turns around re-joins the game. I didn't address this after the game because I had asked a question at half time and he seemed to not want to discuss things with me. I just hope I don't work with him again.