Quettanauts observation.

[palm911]

they dont trade with you , but i saw the paranids trading with them . i assume they do not trade with players but they do with other factions?

hehe

[v_make]

Maybe it's implemented as trade restriction. You are simply restricted from them.
I even tried repeat orders on their stations (you can change the destination after the order is created) but unfortunately did not work.
Quite annoying as their reputation cannot be raised by anything other than station missions.