As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE FLIGHT CREW REPORTED AN OXYGEN SYSTEM LEAK. THE MAINTENANCE VENDOR DETERMINED THAT THE CO-PILOTS OXYGEN MASK WAS LEAKING. THE DEFECTIVE MASK WAS REMOVED AND REPLACED WITH AN OVERHAULED UNIT. DEFECTIVE MASK P/N MLC20-505 S/N 111886. THE DEFECTIVE MASK WAS ORIGINALLY INSTALLED OCT-2018 AFTER OVERHAUL BY AMERON GLOBAL ON 01-OCT-2018. 72 MONTH RESTORATION REQUIREMENT.