Omen of Amelioration does not comsume on death

I just lost 10% of my EXP due to a death penalty while the Omen of Amelioration was active in my inventory. It didn’t consume the item’s stack, and I still lost 10% of my EXP.

Could you please help me check what happened and if it’s possible to restore my 7.5% EXP? It means a lot to me because I spent a lot of time earning it.