As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AIRCRAFT DIVERTED TO TO LHR ACCOUNT OXYGEN LEAK IN COCKPIT. CREW OXYGEN PRESSURE DROPPED -TO 630 PSI, APPROXIMATELY 1.5 HOURS INTO FLIGHT. FOUND O2 MASK STOWAGE BOX AT FAULT. REMOVED AND REPLACED CAPTAINS O2 MASK (AALA202212056511) AND STOWAGE BOX (AALA202212055914) PER AMM 35-11-18 AND 35-11-00.