It will not bounce if all settings are set to zero.
Instead of Bullet behavior, use "Platform Set Vector X" action.
Player On collision with Enemy
....Enemy.X>player.X : Player set Platform Vector X to -1000
....Else : Player set Platform Vector X to 1000
You can add more conditions - if player is on the ground, bounce only to the left or right. If player is in the air, set vector Y as well.