That is strange! Are you sure you talked to the floating fire orb thing in the Guild of Fire and got the quest from it? Because when you check the gem and kill the Queen of Luban-Erya, you're supposed to get a quest completion, and everyone in the active party should learn "Fire Favor" and "Hyper Flare". Are you sure you killed the fire queen? The queen is the one you have to fight to complete the quest, and the fire god is just an extra optional boss. If you already did all of that, then I have no idea what could have went wrong.