Trade not indexing "of the Underground" item.

I cannot get my item to show on trade. When you search for the fractured increased mana reservation efficiency mod, only items with the "of the Essence" version show in the search results. The trade site is not indexing my hat from delve, which has the same mod but with the affix name "of the Underground."

Delve mods and Jewel implicits both use "#% Reduced Mana Reservation Efficiency of Skills" with a value in the right-hand side box.