First, the old gentleman put the Monkey King in the blast furnace to drain water. Just like in Lotus Lantern Prequel, Grandpa Laojun didn't mean to hurt the Monkey King. He just put Wukong in the blast furnace, but left a door so that the Monkey King wouldn't be burned to death at the door, but the three flavors of real fire didn't hurt him. On the contrary, it played an exercise role for him and helped him become a critical eye. The Monkey King at this time, in the face of the real three flavors of true fire, of course, can't fight with it.
Second, when the Monkey King was put into the blast furnace by the old gentleman, although every cloud had a silver edge and became critical, it left a psychological shadow and was afraid of three flavors. So when Hong Haier's three flavors were really hot, the Monkey King was too scared to face them.
Third, it was the Monkey King who escaped the three flavors of Taishang Laojun's blast furnace and became a critical eye, but the critical eye could not resist the smoke of the three flavors, so it could not resist the three flavors of Hong Haier.