Cast on Critical - Eye of Winter not reserving spirit or casting, but other spells work

Not sure what's going on, I had this work a week or two ago but now when I add Eye of Winter into Cast on Critical, it does not reserve mana or cast. The same CoC gem works with other spells, and it shouldn't be a mana or Int issue (using Blood Magic, and have tried with different gem levels of EoW and CoC). I'm open to any ideas, really not sure what is broken here...

I've tried mixing the order of the gems, adding and removing other support gems, etc.

try making another skill gem, it works for me.