As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RED CAS MESSAGE " CABIN ALTITUDE" ILLUMINATED AT CRUISE ALTITUDE. PERFORMED CHECKLIST AND LANDED WITHOUT INCIDENT. PAX OXY MASK WERE DROPPED IN MANUAL MODE. REMOVED AND REPLACED CABIN ALTITUDE MODULES IAW CE750 MM. CHAPTER 45-45-03. OPERATIONAL CHECK GOOD.