No Spring connector - Flat parallel faces option in non-linear analysis

Hi all,

I am trying define analysis with spring connector but I am facing a strange issue.

In Linear Simulation I get Spring connector option wherein it is possible for connector to create a spring between two parallel faces.

Unfortunately, I am unable to see the same option when I tried to simulate the same solution with non-linear behavior option. This flat parallel faces option is not at all available for selection. What seems to be a problem here?

SolidworksSimulation