missing support skill issue

I’m playing Bloodmage with Spellslinger, and I’m getting a “Missing socketed skill” error even though Comet is already socketed.

The skill works fine when I change my weapon, but with my main weapon it doesn’t work and shows the error.

Here’s a screensho

https://prnt.sc/iZZk5kQqdS5V

that's the video
https://www.youtube.com/watch?v=jWIaan7tX_I