Lich with Soulless Form and Eternal Life taking damage to their Ward while having ES

Here is the id from the game for my instance:
Bug Report ID: #2439835490

Normally, I do not take damage to my life for as long as I have ES. This is how Soulless Form and Eternal Life works together.

But right now, I wanted to "heal" my life by letting small mobs hit me, remove my ES so I could use a potion. But I noticed my Ward going down as I get hit. If my Ward is under my life and I have ES, how is that even possible?

I made a test: if I removed Eternal Life, heal at the well, then add it back, Ward is no longer taking damage.

So the issue is why you do not have enough life to cover what goes through your ES it seems.