Why am i only breathing out of one nostril?

Breathing through one nostril can occur due to several reasons, including nasal congestion from Allergies, a cold, or sinus infection, which can cause swelling and block airflow. Additionally, the nasal cycle, a natural process where airflow alternates between nostrils, could make it seem like one nostril is more open than the other at times. If the blockage persists or is accompanied by other symptoms, it may be a good idea to consult a healthcare professional.