As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DESCENDING AT 9000FT CREW NOTICED CABIN WAS CLIMBING. NO FAULT LIGHT ON THE PRESSURISATION CONTROLLER AND BLEED AIR CONTINUED TO FLOW. CABIN DIFFERENTIAL REACHED ZERO AND THEN THE CABIN DESCENDED AT THE AIRCRAFT RATE OF DESCENT. NO CABIN PRESSURE WARNING AS THE AIRCRAFT WAS BELOW 10000FT. BESIDES THE CABIN PRESSURE CONTROLLER, MAINTENANCE ALSO REPLACED AFT OUTFLOW VALVE.