As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. EMERGENCY DECLARED. DCA-MIA FLIGHT RETURNED TO DCA ACCOUNT LANDING GEAR NOT RETRACTING INDICATION. UNEVENTFUL LANDING. DISCOVERED ALTERNATE GEAR EXTENSION DOOR OPEN INTERFERING WITH LANDING GEAR RETRACTION. VERIFIED PROPER OPERATION OF DOOR AND SWITCH IAW AMM 32-34-00. OPERATIONAL CHECK GOOD.