As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURN BACK SEA FLT 7202, CARGO DOOR VENT OPENED AFTER TAKEOFF. PILOT RETURNED TO SEA. MAINTENANCE ACCOMPLISHED INSPECTION AND OPERATIONAL CHECK OF CARGO DOOR LATCHING AND LOCKING MECHANISM. REINSTALLED ACCESS PANEL. PERFORMED HARD LANDING INSPECTION DUE TO RETURNING WITH DOOR WARNING. NO DEFECTS NOTED. AIRCRAFT RETURNED TO SERVICE.