Commercial Fixed Wing
Dispatch Dispatcher
Communication Breakdown
Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance
Flight Crew Overcame Equipment Problem
Human Factors; Procedure
Flight XXX was a little north of ZZZ when I got called by Load Planning saying there was a piece of Hazmat that was loaded and not reflected in the weight manifest. There were two pieces of Hazmat for this flight with piece 2 was supposed to be held off. When the original weight manifest was done; both pieces were reflected to be held off when piece 1 was loaded in pit 3. The flight took off and Cargo made a call to investigate and that was when the mistake was discovered. An updated pilot notification and weight manifest change was sent to the flight crew when the flight was a little south of ZZZ.
Airline Dispatcher reported receiving corrected Hazmat cargo weights after aircraft departure. Updated Hazmat data was sent to aircraft.