A 48 year male is case of allergic rhinitis since last 10 yrs, bilateral turbinectomy was done 4 years back, for entrapped mucocele ethmoidectomy done 2 years back, now having left side nasal discomfort with mucoid discharge, sinuscopy nothing significant CT PNS showing hazziness in left frontal and ethmoid sinus, patient is taking nasal spray with montelukast with some relife. What could be the further management?