Solved Stone walls keep breaking on my server

Hi all.
Sorry for my english, but i try to explain you my situation.
There are the stone walls are breaking very often on my server. When the players put the wall - it has a blue form, but it crashed very often when they put it on the ground. How can i solve this? Is that a stability problen or what?
Instant. just put, and it has breaks. Maybe it is a relief problem? Because the player put another wall near this place - and it puts normal.
And it is not an entity limit.

When the player install the walls - it crashes often, and when i do it, it is don't crash. I am the owner and admin, he is only player

watch from 25 second

 

I thinks it's a stability problem.. But I don't know how to fix this.. maybe you can disable stability with a plugin and try it out aigan?

 

That was a problem with the plugin - Building Blocker. It has wrong configured.

 

might it be decaying?