2D Paper Character - Fly when colliding

Hello
I have a little problem when my player character(which is paper character also) at walk speed (1000) collides with a zombie from bottom or top then like a hook it takes the zombie then releases it at some point after that character flys to the some direction.
Zombie and player has character movement on “walking” and physic interaction is closed soo how can this happen? what should i do?.I want to prevent my character from pushing the zombie with him.