Die in the End while fighting the Ender dragon make him no AI when the player come back to the End

When the players go to the End and died while try to kill the Ender Dragon. When the player come back to life and went back the the End the Ender Dragon have no AI, can’t be hurt, or attack the player. the way back the the overworld is lite, the Ender egg was there. The player go to the over world and then back again to the End the Ender Dragon disappear