Life Barrier with Heroes?

I really want to know WHY i cannot make monk heroes with life barrier working.

Whenever i cast it,it removes instantly? Can anyone explain this

Hold shift, then click the skill on the hero's skill bar. Select the target you wish to enchant in the party bar, and click the skill on the hero skill bar to activate the maintained enchantment.

You must disable maintained enchants for heroes, or they will immediately cancel them once cast, with few exceptions.

Hero AI will not maintain enchantments unless they see them needed - they will only cast them in combat and cancel as soon as the danger is over. Thus, it is not possible to pre-prot or prot the whole party normally.

You can get them to do it manually, though. Disable the skill (shift click on the bar, a red sign will cover it), so the AI will not use it at all, then order the hero to use the skill (select the intended target and click the cancelled skill - the red sign must remain!). The hero AI won't cancel the skill.

Remember you'll have to do it manually.