Pax feedback to station staff(YIS) RearM1 car train doors did not opened. Staff (SBW) checked and c onfirmed no abnormalities with train doors. Doors opened andclosed as per normal. ~~~~~ 1614 Pax feedback to station staff(YIS) train doors did not opened. Staff (SBW) confirmed no abnormalities with train doors. Doors opened and closed as per normal. CE found 1614 B2 door intermittently unable to Open and Closed with a dragging sound. 1614 B3 door 0pen/Closed Ok Depot 1614 train door operational check.  1614 Checked no door FC . Checked 1612 B2 LHS door leaf outer roller delaminated. Replaced roller. Door gap, guide, weather dtrip checked ok. Door lock switch checked ok.  Redzwan/Aliff 45225