Phlegm taste in mouth and breath. pain in sternum. no cough or cold just sometimes clearing of throat.

Phlegm in throat: Phlegm in the throat associated with throat clearing and heartburn symptoms sounds like acid reflux. Generally treatment would start out with acid avoidance (citrus, tomatoes, peppermint, coffee, peppermint, etc) Acid irritating the throat frequently results in increased mucous and prompts throat clearing. I advise increasing water intake and consider starting an antacid. See your doctor.