As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT CREW NOTICED THAT TH BOTTOM DECOMPRESSION DOOR ON THE MAIN CABIN DOOR IS NOT SECURED. SEEMS THAT THE LATCHES ARE NO LONGER KEEPING THE DOOR CLOSED. RE-SECURED UPPED DECK CREW SERVICE DECOMPRESSION DOOR AS PER AMM 52-13-01/401. NOW OK.