Abyssal lich ascendancy bug?

In ascendacy, I have Enternal life "Your life cannot change while you have energy shield"

I was trying to do a hexblast build which did not workout at all for me xD and saw that I can use "Extraction" support gem which sacifice a portion of life in exchange for extra chaos damage (I boosted my damage and my life did not changed), but other support gems like convert mana cost to life cost do not work at all.

It is bug or it should work that way? As I have 34 lv hexblast it is very hard to sustain mana :/