So yesterday we kill first boss on HM KP, someone had to leave. so we started again tonight. someone went in before i set it to hardmode. He came out i reset it and put it on hardmode. But we had to kill first boss again He had normal mode hp. So we killed it then i checked and i was locked normal mode.We all left just to make sure. It was set to hard mode. Relogged tried everything can't get it out of normal mode no matter what i put on the door.
TLDR- ops stuck in normal no matter what i try.