Chronic phlegm with no infection?

I ALWAYS have phlegm, and no matter what I try, I cant never actually get rid of it. If I use tea or warm water, I get all of it up and out, but its back within an hour. Im 99% sure I dont have an infection, because this has been going on for years, and it's the only thing, I have no breathing problems, or soreness, or anything, just alot of phlegm. Is there any way I can permanently get rid of it?