Train doors at Front M2 car B1 door notproven closed. TC recycled few times to no avail. Staff (CTH ) assisted to push closed for train to depart. Staff later f eedback there was a 2CM gap. SM (MRB) later isolated affecte ~~~~~ 2530 B1 Train Doors Not Proven Closed. Level 3 CTH SB: TC reported 2530 B1 train doors not proven closed. Staff CTH board the train & feedback there was a 2 cm gap. Staff assisted to push close for train to depart. IMCC informed. ID: 2.5mins. (sent at 09:11 14-Feb-2024)" CE checked : 2530 B1 was isolated with sticker. L3 2530 B1 door Fault duplicated in depot. From ER observed TC cycled doors 4 times before staff push door to close fully. Checked and found door isolated. Normalized and found #2530 B1 RHS door unable to close completely with a small gap. Removed door leaf and found outer roller had a cut and protrusion. Postulate that the protrusion acted as an obstruction on J rail causing RHS door to not be able to close fully. No FOD was found along guide rail & J-rail. No door rubbing marks observed. Weather strips are secured. Condition of weather strips are good. No abnormal noise from J-rail. No air leakages from actuator and manifold in open/closed position. Replaced both #2530 B1 RHS rollers. Cleaned J rail & function check door operation √ SATIS. Perform 10/20 mm gauge test √ Passed. Door cyclic test 20x √ ok. Door open/close timing √ ok.    Door manual force check √ ok. Check EMV for any residue voltage when door close √ ok.  Justin Kua 45336