Passenger feedback to staff(ADM) of thedoor window external rubber gasket has partially broken off and is loose in car 2540, A4 or B4 train doors. Staff (KTB) checked but unable to locate. ~~~~~ 2540 Passenger feedback to staff(ADM) of the door window external rubber gasket has partially broken off and is loose in A4 or B4 train doors. Staff (KTB)checked but unable to locate. #Train was scheduled withdrawal to depot.  2540 exposed weather strip rubber trimmed. Tested door operation - OK. Wong/Kiran/Shamil/Akira 45051