As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PASSENGER DOOR HANDLE MESSAGE DURING CLIMB THROUGH FL220. WHILE PERFORMING QUICK REFERENCE HANDBOOK PROCEDURE, PASSENGER DOOR WARNING MESSAGE CAME ON.REMOVED GRAVEL FROM DOOR SEAL, DEPRESSOR AND SILL AREA, DOOR CLOSED AND CONFIRMED STOWED AND LOCKED.