Why is the AC only blowing air through the top vents?

If your AC is only blowing air through the top vents, it could be due to a malfunctioning mode door or blend door actuator, which controls airflow direction. Alternatively, there might be a blockage in the ductwork or a problem with the control settings. Additionally, low refrigerant levels or issues with the AC's compressor might also contribute to uneven airflow. It's advisable to have a professional inspect the system to diagnose and resolve the issue.