Eternal Life + Blood Magic not working

I think this is a bug.

I've Blood Magic passive, and when I activate Eternal Life in Lich Asc, my spells cannot be spelled, even in full life.
There's a red spark in my head and not cast any spell.

This is not actually a bug. Eternal Life specifies that your life CANNOT change while you have energy shield. Blood Magic makes your spells COST life. Since your life cannot change, you cannot pay the cost to cast spells with blood magic.