You will have to consult ENT specialist
and get done CT scan of nose and paranasal sinuses
to see if there is disease in the sinuses or there is leak anywhere.
After that it will be possible to comment on the further treatment .
YOu can start with antibiotics like roxithromycin
and nasal and oral decongestants.
Nasal sprays like normal saline sprays and steroid
sprays can be planned to use after the scan.