As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - CREW REPORTED AIRCRAFT LOST PRESSURIZATION AND NOTICED THE CABIN ALTITUDE CLIMBING. DECLARED AND EMERGENCY AND DESCENDED, O2 MASKS DID NOT DEPLOY. EMERGENCY DECLARED RETURNED DFW WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED BOTH PRESSURE CONTROLLERS. SYSTEM GROUND CHECK NORMAL OPERATION.