I constantly have chest phloem. why? is it the inflammation from asthma?

Allergies: Or increased mucous production. See your doctor and be evaluated to see if they can help you.

It may be: Inflammation form asthma nay cause a reactive airway disease manifestation of mucus/phlegm build up. Allergies, smoking, and possible infectious processes can also predispose one to phlegm production. If troublesome, seek medical attention for treatment options. Best wishes.