How To Cure Congealing Of Discharge In Nasal Space Post SMR Surgery?

As a 76 yr old male, have had SMR surgery 40 yrs ago, and was left with hyper active sinus discharge from left sinus. Over the intervening years, had another surgeon attempt to relieve symptoms, but ineffectively. Since 1995 the symptoms have worsened, and now suffer a discharge which congeals in the nasal space at the high point, and every 2 days, I have to resort to very blowing and physical digital extraction to remove the obstruction which interferes with breathing and the asthma I have had since 1968. The asthma cough increases during the second day of the obstruction becoming noticeable, but at this juncture, it is not possible to remove. The eventual removal shows a almost black mass of congealed mucus, approximately 20 x 10 cm, looks like a garden slug.. Doctors cannot find any means of effective control or treatment of the obstruction. Tried various drops but none work. What is answer ?