As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DURING CRUISE CABIN ALTITUDE BEGAN TO CLIMB AND COULD NOT BE CONTROLLED IN AUTO. INITIATED EMERGENCY DESCENT AND FOLLOWED QUICK REFERENCE HANDBOOK PROCEDURES FOR RAPID DEPRESSURIZATION. CABIN OXYGEN MASKS MANUALLY DEPLOYED. REMOVED AND REPLACED OUTFLOW VALVE PER AMM 21-31-03. OPERATIONS CHECK GOOD PER AMM 21-31-00. REMOVED AND REPLACED BOTH CABIN PRESSURE CONTROL MODULES (AALA202110063947) (AALA202110063377) PER AMM 21-31-02.