As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF FROM ATL AT 10,000 FT ACCELERATING THROUGH APPROXIMATELY 280 KNOTS, FLIGHT ATTENDANT ON AFT JUMP SEAT REPORTED A SINGLE BANG FROM LEFT SIDE. AFTER LANDING, AFT SERVICE DOOR WAS MISSING. SUSPECT APPROX 20 NM NW OF KATL. RELACED AFT LAV SERVICE PANEL DOOR.