If the nose block is remaining for just 6 to 8 hrs or so it's a normal nasal cycle which all humans have. If u noticed it lately u need a simple antihistaminic to reduce the congestion.
Ideally take steam inhalation if u feel so.
Next Steps
if it's for 6 to 8 hrs it's normal cycle.
if not then take steam first than directly jumping for medicines
Health Tips
try sleeping on the side which is blocked if it opens its a normal.