Slimes Will Not Attack and Bounce in One Direction

What I expected to happen was...:
I expected the slimes to attack me when I came near them

What actually happened was...:
They won't target you; even if you purposely walk into them they won't do damage. They face one direction and bounce forward and won't do anything else.

Steps to Reproduce:
1. Spawn a slime
2. Go into survival.
3. See that it is not attacking you.