My animals get stuck on fences.

I think there is a problem with fences? As you see in the picture, my character is holding seeds which is an asset for breeding chickens. 2 of the chickens I have follow but the little chick on the corner of the fence does not. When I get nearer it follows but then its movement is only limited to where the fences are. It does not move to other block areas. It also happened with one of my pigs, both got stuck on the fences.