Train doors were not proven closed. TC opened and closed train doors twiceto no avail and confirme d 'A2' door at FDT car was not proven closed.Staff (YWT) a ssisted to push close the door for train to depart. Fault re ~~~~~ Train doors were not proven closed. TC o     Checked found #3645-A2 door LHS roller faulty. Replaced ok and door function and cyclic and static test ok. All doors timing within criteria. Done by Koh. 16/05/22