As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A LOSS OF CABIN PRESSURIZATION WHEN CLIMBING THROUGH FL210. CABIN ALT WENT ABOVE 10,000 FT DURING DESCENT. MAINTENANCE REMOVED AND REPLACED THE E1 HIGH STAGE AND PRESSURE OUTFLOW VALVE IAW MM. OPS CHECK WAS GOOD AND AIRCRAFT DID A FUNCIONAL CHECK FLIGHT. AIRCRAFT WAS THEN RETURNED TO SERVICE. (K)