As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE AT FL 390, MAIN DECK CARGO DOOR DEVELOPED A SQUEAL AND CABIN ALTITUDE BEGAN TO CLIMB. DESCENDED TO FL 330, DOOR STILL SQUEALED BUT CABIN ALTITUDE STABILIZED. PRESSURIZED ACFT TO 7 PSI DIFFERENTIAL AND FOUND SEAL ON MAIN CARGO DOOR LEAKING WHERE JOINED AT AFT LOWER CORNER. RESEALED JOINT IAW AMM 52-09-04. OPS CHECKED GOOD.