BP Construction Scripted called 4 times

I noticed an issue while making my spline road BP.
today I wanted to make a Fence BP to create a fence with it.
The problem is that the CS is called four times, I have some weird looking rood meshes because it spawned 4 times each spline point and my attempt to make the fence BP failed because of that issue.
How can I fix that?

An already made a new BP with just a Print String in it, to be sure that it is called multiple times. and yes it does!