Allays get stuck in the ceiling

Allays get stuck in the ceiling made of slabs

What I expected to happen was...:
They follow me

What actually happened was...:
They're stuck for some reason

Steps to Reproduce:
1. I made a house for my Allays but the floor it's made of slabs
2. When they have no items in their hands and they wander freely they randomly get stuck in the ceiling
3. When i give a cookie or any item for them to follow me they won't move for some reason

 

Thx for your attention. (sorry for my horrible English)