It's okay, i try to ask forum but no one is answering my question XD
The bug trigger after "State" effect is popup whenever get buff or debuff "State"
Example: When i want to add Magic dmg bonus buff using skill, "State" Magic attack bonus buff is popup and the error is trigger as "ElementID is Undenfined"
So i guess "State" is define as "Element" but when i try to add "Element" on "State" nothing change