Unal Engine 4 Npc disappear

Hello All ! need help ! my NPC characters began to disappear when they approached me, before that was not like this , had anyone ever faced this before? this is my Npc blueprint file : SimpleAi.uasset - Google Drive and this a video

I found the cause of missing NPCs , I followed the (TorQueMoD - from youtube) - Enemy Health System Tutorial in it the mistake of the one who taught it, the ActorDeatch event led to the destruction of NPCs, even when they were not attacked and the health was 100% i tried everywhere instead of DestroyActor changed to PrintString and found in “ActorDeatch”