Cast on Elemental Ailment not reserving Spirit / “missing socketed skill”

I’m having an issue with Cast on Elemental Ailment where the gem does not activate at all.

- The gem shows “missing socketed skill”
- It does not reserve any Spirit
- It does not trigger under any condition

What I tested:

- Socketed multiple spells:
Spark
Arc
Fireball
Comet

- Tried with and without support gems
- Confirmed I have enough Spirit
- Removed secondary weapon (tested with only one weapon set)
- Re-socketed everything from scratch
- Moved the setup to different gear pieces
- Relogged / restarted client

None of these changed the behavior.

Expected behavior:

The gem should reserve Spirit and activate when a valid spell is socketed.

Actual behavior:

The gem remains inactive and shows “missing socketed skill” regardless of setup.

This makes me think either:

the gem instance is bugged, or
Cast on Elemental Ailment is currently not functioning correctly.

If anyone has this working, please let me know what setup you’re using.

Thanks!

reference ID: 3.023.150.363.

The gem I bought from the market was "broken", "bug", or something, bought a new one and now it works fine!