Diagnosed With Pneumonia After Hazed Opacity Found In Lower Lobe. Chest Clear But Why Having Pain And Cough With Phelgm?

Hi, I've been diagnosed to Pneumonia 3 months ago. There was a hazed opacity seen on my right lower lobe. After 2 weeks of medications and check ups, my last x-ray results showed that my lung fields are essentially clear. After one month, i still can feel the slight pain on my lower right chest same as before. and now i have cough with phlegm again... I'm confused, i was clear but why why i can still feel the pain on my chest?