@reddy It might be allergies. I have asthma triggered by allergies, and my other post talks about my symptoms and issues. I think I have it figured out now. My issues all start with allergies that cause the build up of phlegm and can progress to being an infection. I have 3 cats and am very allergic to them. I found a way to cope with that with extra cleaning to remove dander, wiping my cats with a wet washcloth (they are not fans of that) a HEPA filter that also has carbon filtration next to my bed blowing on me, and wearing a good quality surgical mask when I sleep that is rated at 99% efficiency. We are more vulnerable when we sleep because we are not clearing phlegm like when we are up and moving around. You can try wearing a mask and see if it stops your phlegm buildup and then you would know where to start. My mask are made by 3M #1829 Procedure mask with >99% @ 0.1 Micron particles which is equivalent to a HEPA filter. they have ear loops and are comfortable to wear. I bought them online form Walmart. I also do allergy shots and/or antihistamines. Having chronic excess phlegm does set you up for lung infections because the bugs love it.