There’s a relation between dust allergy and polyp formation, however deviated septum is a co existing problem which as you rightly said contributes to nasal obstruction along with the polyps.
Polyps need removal with surgery and then avoid reformation by avoiding exposure and use of nasal sprays.
The nasal sprays used for allergy are NOT SAME as the ones you are probably using ( they do not cause rebound congestion) kindly do not use anything without a consult.
Surgery is unavoidable if your symptoms are severe and you seek long term relief. Post surgery you need rest for about a week and then you can resume your work ( except physical exertion) * depends on type and extent of surgery and recovery speed which varies from person to person
Next Steps
Online / in clinic consult for further guidance
Health Tips
Do not use OTC nasal sprays it may worsen your nose block symptom