Today I noticed, that I can create a palisade piece on top of it, but when I place a piece next to it, it also loses grid and cannot be completed.

I took a shovel and dug down thinking that maybe hitbox is somewhere underground or I could make the piece detach itself as a dynamic object. I discovered I caninteract with the object FROM BELOW. I was able to deconstruct a piece.

MEbug3.jpg (783,567 bytes)   

MEbug3.jpg (783,567 bytes)   

After deconstructing the buged palisade pieces, I am unable to place a palisade in the exact same spot.

After deconstructin all of the buged pieces, I was able to place palisade correctly. All pieces were not buged.

Can you confirm if the issue you are seeing is 0000122?
It sounds like the same issue, but you didn't mention a key trigger for the issue: removing a block.
The bug above happens if you build a grid, and then remove a block, causing the grid to split. When that happens one half of the grid will be "dead", which behaves exactly as you mention.

Can you confirm if you did remove a block causing it to split before it stopped working?

I think I did, yes. I will make a test to confirm this. Although I remember splitting the palisade into two earlier on, and not seeing this problem.

Going to close this as a duplicate of 0000122 since the symptoms sound extremely similar and I can't reproduce this on CE after fixing it.