Pax feedback to staff(AMK) that one of the train doors did not open at car 1614 "B3" door . Staff(KT B) confirmed and isolated the defective 'B3' doors at car 16 14 in close position. ~~~~~ 1614 B3 door LHS stuck at certain position. Removed door & found both LHS door leaf rollers faulty'.  Replaced both rollers. RHS door opening/closing was smooth. Door cyclic test - OK. Cleaned J-rail/guide rail, no FOD was found. Door open/close timing, door gap 63.5mm & weather strip checked - OK. All doors proven closed & no DIR lit up.  Sarma/Alan/Lee PT/Kamarul. 04/03/2023.