TC reported MCH stuck at 'B3' position.TC toggled to clear fault. ~~~~~ FAULT DUPLICATED DURING RECTIFY FAULT ONLY OCCUR WHEN MS IS IN ATPM.OBSERVED THAT MS DOES NOT SPRING BACK WHEN PUT TO ATPM POSITION ,REMAINING IN AN OVER TRAVELLED POSITION PREVENTING MCH FROM MOVING.FURT CHECK FOUND A PIECE OF TISSUE PAPER WEDGED BETWEEN MS INHIBITOR AND MS HOUSING.REMOVED FOD,CLEANED INHIBITOR AND ADJOURNING SURFACES OK.CARRIED OUT CYCLIC CHECK 20 TIMES FAULT DID NOT REOCCUR.BASSANT 24.02.2022