How to get rid of post nasal drip

Patient: Hey so far i have had post nadsl drip for about 2 years now and im sick and tired of having it now so far i”ve been to the doctor and they prescribed me a nasal spray but that really didnt help . Also i’ve been having this evrry day for 2 years. some times it”s really bad and other days its tolerable At least every day i”ve mad a routine to blow my nose frequntly and even gargle salt water. But nothin has worked please help me bEcause i dont want this for my whole life