Skill at selling items remotely. Each level increases the range from the seller to the item being sold. Level 1 allows for the sale of items within the same solar system, Level 2 extends that range to systems within 5 jumps, and each subsequent level then doubles it. Level 5 allows for sale of items located anywhere within current region.
means you can be somewhere else and put the stuff you have elsewhere onto market. That is, without having to be in the station yourself.
you can not sell stuff to another station unless you bring your stuff to that station yourself unless that buy order is set for more than npc range (station).
so, the skill is working (should be), but not as you expected unfortunatelly ...