As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW AND ALL JUMPSEAT OXYGEN MASKS WILL NOT TEST. FOUND NR 1 COURIER MASK NOT STOWED. RESTOWED ALL MASKS, CHECK OK. NR 1 COURIER 02 MASK INOP. ENTERED DEFERRAL M274961 MEL 35-31-01 PLACARD INSTALLED, SEAT MUST BE UNOCCUPIED. REPLACE 02 MASK PER MM TESTS OK CLEARED M274961.