TC reported Rear M1 car, B2 door not proven closed. TC opened and closed a few times to clear fault.Fault recurred at SOM2 and DBG2. Staff(RFP) assisted to iso late the faulty door in closed position. ~~~~~ TC reported Rear M1 car, B2 door not pro     #1613-B2 door FC 953 X 3,Door was isolated.No FOD found on rail.Cleaned guide rail & J rail.Conduct door function check found DLD did not go down-replace DLD ok.Door static test within criteria. DLD c/o- Old: C151 BDL 148030 New: C151 BDL 147043 Not: 2408967 Done by Haslan/Asruddin.  17/08/22 1613 B2 To remove door and check roller #1613-B2 door remove,Found LHS roller damage and RHS abnormal    sound.Replaced both door roller.Function check and static test-tested ok all within criteria. Done by Saini/Haslan. 17/08/22