The a/c blower is not directing the air to the top side. Only to the floor. Does that sound like an easy fix ? It’s a '99 Astro
The fix could simply be to reconnect a vacuum hose that has slipped off of the servo motor that redirects air flow. Or, it could be a servo motor that has died. Either way, the toughest part is getting into the confined areas of the dashboard to access the problem parts.