Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Communication Breakdown
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural FAR
General None Reported / Taken
Human Factors; Procedure
When airborne; we were notified by our Dispatcher that one of our positions had dry ice that was not accounted for in the DG [Dangerous Goods] paperwork.Uncertain as to the cause given the event occurred at some point during the loading or ULD [Unit Load Devise] build process.Uncertain; as the process breakdown occurred external to the flight crew.
At XA:31 [name 1] informed me that Aircraft X; position Y; had 6kgs of dry ice that was not accounted for in the DG [Dangerous Goods] manifest.  The flight was on the active runway ready for take off. At XA:31 I informed Duty Officer [name 2]; of the event. I also told him I would inform the crew via ACARS.  We agreed the flight is still legal; it is safe and within limits. Aircraft X may proceed to ZZZ1.  At XA:32 I informed [name 1] of my discussion with the Duty Officer. I requested from [name 1] the Ramp Agent's employee number #X; [name 3].  At XA:44 I sent an ACARS message:  'Hello Aircraft X. At XA:31 I was made aware that position Y has 6 kg of dry ice that was not accounted for in Dangerous Goods [manifest]. Duty Officer has been notified. Please file a report; I will be doing the same.We have determined that the flight is safe; legal; and within limits. I called [name 3];to inquire about the event. [Name 3]; said it was a can from ZZZ2 that came in from another area; when the Hazmat agent updated the DG summary the aircraft had already blocked. [Name 3]; received an alert and called [name 1]. [Name 3] the can was originally assigned to a can aircraft cargo container type that is not in this aircraft's configuration for this flight. It took the Hazmat agent time to correct it; he entered the information after the aircraft blocked.I suggested Hazmat agent make a phone call to Operations or ramp agent as soon as he encountered the error rather than trying to figure out how to correct the error and entering the information in the DG Summary after the aircraft blocked.
Air Carrier Captain reported Dispatch notification of Hazmat documents violation while airborne.