The report says that the Autobrake fault was due to a faulty servo valve for one of the 8 main wheels(Indian Airbus): "During approach when the landing gear was selected down “Brake Auto Brake Fault” ECAM warning message was triggered at 0642 UTC with failure message of “BRK NORM SERVOVLV7 (80GG)”.
Later in the report, it states that braking action was reduced due to the loss of the servo valve: "High pitch angle at touchdown, prolonged flare and low response of braking action due to the failure of servo valve along with the improper application of emergency checklist resulted into increase in the landing distance and runway overrun at Jammu airport."
One would think that losing only one of seven servo valves would hardly be noticable for the difference in braking capability.