The report concludes that the aircraft, on its first approach, encountered a gust of sufficient intensity to produce asymmetric movement of the flaps. The asymmetric movement caused the flaps to lock and generated a "FLAPS LOCKED" message on the EC AM. By selecting the FLAPS lever to Config 3 as directed to by the ECAM the lateral control law became sensitive when the flaps were locked in the Config FULL position (40°) and hence rendered the aircraft difficult to control in roll in turbulent conditions.
HongKong Dragon air accident in 1994. Where they had flaps jam at full and go around in lever3 and subsequent three more approaches with lever3 caused severe oscillations. Since then procedure was changed to do approach in full if flap jammed >3.