Tend to lay down after I eat. An hour or less after. And snack in bed. May have acid reflux symptoms, not GERD, but lpr version. Throat, phlegm. Even sinus issues and cough. Could this be the reason?

LPR differs from GER. LPR is similar to GERD. LPR, you may not have the classic symptoms of GERD, Heartburn. That's why it can be difficult to diagnose and sometimes called silent reflux. In LPR Upper & Lower esophageal sphincters do not work right,
Silent reflux is common in infants because their sphincters are undeveloped, shorter esophagus, and they lie down much of the time, In adults etiology is unknown.