As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF THE CREW DETERMINED THE GROUND COMMUNICATION DOOR WAS OPEN. THE FLIGHT RETURNED TO CLT AND LANDED WITHOUT INCIDENT. MAINTENANCE CONFIRMED THE OPEN DOOR. INSPECTION REVEALED NO DISCREPANCIES. THE DOOR WAS PROPERLY SECURED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.