Copper Citadel Map Failed

Hello,

Yesterday I run the copper citadel even though I killed the Ferudun at the end it said map failed because there was this rare monster left. Since you changed the area on the boss fight it did not let me go back to kill it. But I was pretty sure there was no rares left. And same thing happened in one of my maps with map boss. Map Boss was Mektul, The Forgemaster and after I killed him it didnt let me go back up to fully clear and just failed.