This is usually a viral infection (URI)so mostly subside by itself
Next Steps
if having more severe causing trouble then can use
1. saline drops(nasivion -S ) 1 drop in each nostril 3-4 times a day, there is no harm of using it
2. steam inhalation
Health Tips
If still not improving can use maxtra drops 5 drops thrice a day( if weight is approximately 8-9 kg)