@jbix, are you sure you are nebbing 9% saline? Don't you mean 0.9% saline? If 0.9% saline, you might want to up your game with 3%, then later 7%. It should make a difference. Some people drink organic green tea or organic mullein tea (I drink both, that helps). And of course, exercise is quite helpful for expectoration, especially if you push outside of your comfort zone. Some people do percussions on their chest too with various accessories purchased off Amazon, some have success with this.
Best wishes of great health to all of us!