Experience and hours being lost- Amelioration no proc on death (several times now in endgame)

Several times the Omen of Amelioration has been activated in my inventory and failed to proc at death while playing endgame. I don't understand if I am missing something, but watching like 12% of your bar disappear in the mid 90's is beyond frustrating....hence buying the Omens and hoping to avoid the rare occurrence.

Anyone else experience this?