Sheeps phasing through walls

[rocky0121]

My sheep keep phasing through walls and getting out of their enclosure, I asked either Tiat cutout or nevlo about it and they didn't know what to do. The walls are glass and it could have to do with the fact that glass is categorized as "transparent blocks" in mc, however, the same problem occurred when the walls were cobblestone (opaque block) only difference being that the sheep suffocated and died.

[martinjonsson01]

Is the pen overcrowded, or do the sheep just walk into the walls?

[rocky0121]

its not too overcrowded, the sheep do walk into walls

[JC3371]

I can account for this as well