TC reported 'B' side cab door keeps opening again after closing following standing train protection.TC attempted to close cab door again thrice - ok ~~~~~ #3622 FAULT U BLE TO DUPLICATE IN DEPOT.CHECK AND FOUND SLIGHT AIR LEAKING ON MANIFOLD ON ADJUSTMENT SCREW.RETIGHTEN NO MORE LEAK.CHECK THE LOCKING MAGNETRIC SWITCH,LATCHING MECHANISM WITHIN CRITERIA.CHECK FOR FOD NIL.CLEAN RAILS OK.COMPLETED DOOR TIMING PASS ABLE TO LATCH CYCLIC 10 TIMES OK.DIR ABLE TO EXTINGUISH.HAKIM 18.03.2023