Monster killed, but didnt Die

hello in my mapping t15map elite monster been killed by me but after death he didnt Die lol, he was still chasing me, doing dmg to me but i couldnt kill it again(and im not talking about after death shadow that walks and toss skills like in PoE1), because it was elite my map didnt count as finished aswell, nothing i did allowed me to kill him Again(tried monk bell and other aoe skills) so i had to use another map on the stage to reset it