Looking for a title

It’s a manwha where girl gets transmigrated into a story where the ogML was a slave who was “guide” for a king who had powers. (Maybe a pillar of fire??). Anyways she’s the kings doctor and is trying to cure (?) him but we find out ogFL was actually trying to kill the king. So new FL turns out to know the story, saves the ogML and sets him free (he was the prince of another kingdom??) and it turns out she’s the kings guide in this TL. I’m pretty sure the villain is a blonde duke who ogFL was working with. I’ll prob be able to answer questions. I was reading this then all my saved readings were mass deleted :(