I have persistent cough for 2 years and spit up clear bubbly phlegm. if i lie down i choke and gasp for air until i sit up and cough & catch my breath?

See doctor: Any cough lasting more than 2 weeks needs evaluation. Two years is too long to wait. You ought to see a doctor, preferably a pulmonoligst, for examination. If is not feasible to provide a meaningful opinion without examining you and may be conducting imaging and laboratory studies. To be blunt, tuberculosis needs to be excluded.

Laryngospasm: Sounds like laryngospasm from decreased sensation of the larynx from chronic acid reflux. See an ENT.