Welcome to HCM,
Initially after nasal surgery due to congestion and swelling on nasal mucosa, this problem is common.
Gradually congestion and swelling on nasal mucosa will be reduced and you will have clear air way.
I think you might be on some antibiotic, decongestant and anti inflammatory medicines.
You may take Vicks
vapor nasal inhalation or put decongestant nasal drops.
Ok and bye.