Sinus Medication Solution

I have sinusitis for the past 15 years and it is getting worse on and off.. it depends on the food sometimes like Ghee and vegegable salads makes worsens the nasal blocks

I have nasal block almost all the time and I use Otrivin nasal drops to get relieved I can say that I am adicted to it

if it is more worst I use Rhinocart a Steroidal nasal spray to get quick relief and it works only some weeks or months then gets worse. Doctors adviced me FESS (functional endoscopic sinus surgery) but according to the doctors’ openion this will work for few months and I will have the same problem when infection arises.

is there a permenant solution to it can some one help me that leads me non-surgical permenent healing…