Train doors at Rear M1 car 'B2' door were not proven closed. TC recycled train doors once - ok. Staf f(BNL) checked and confirmed no train doors abnormalities. F ault did not recur at subsequent stations. ~~~~~ CHECK CAR 1633 B2 DOOR FOUND LHS OUTER MAIN ROLLER DELIMI TED REPLACEMENT DONE.RHS OK.DOOR FUNCTION TEST AND CYCLIC TEST OK.DIR ABLE TO EXTINGUSHER ON CLOSE.HAKIM/SHAIK 08.06.2023