Died in Sanctum Run with Moment's Peace Boon

Hi,

Im running Sanctum trial trying to get my 4th ascendancy. I'm a Bloodwitch and I know about its characteristics. I received a boon called "Moment's Peace" where it says, "You CANNOT be damaged until you completed the next room" Apparently, somehow I died in the room. There was a ground effect from one of the rare mob that killed me. And no, it's not over casting my HP pool either. Please Fix this!