Mucus is normally swallowed unconsciously, but when there is a feeling of the mucus gathering in the throat or dripping from the back of your nose, it is called post-nasal drip.
Feeling of lump in the throat

GERD and LPR
When acid refluxes from the stomach into the esophagus, it is known as gastroesophageal reflux disease (GERD). If stomach acid travels up the esophagus into the throat, it is known as laryngopharyngeal reflux (LPR).
Dysphagia
Dysphagia means that you can’t swallow well. Many factors may cause dysphagia, and most are temporary and non-life-threatening.