Lost control of the curve ball


My 14u son had a very good curveball. Until this past week. His command of the curve has left him. All at once. Just gone. It’s flat, faster and spins away from the catcher uncontrollably. Pitched twice last week, same thing.
Any tips for how to get it back?


Did he throw a slow curve before? He could simply be over throwing it or choking it. Have him get back to the basics of spinning the ball. He can use a tennis ball can or something similar and practice getting good end over end rotation of the can, then apply that same arm tempo with a ball.