Train doors both side unable to close. TC open and close few times to no avail. TC open and close ca b door 'B' side - ok. ~~~~~ L3 3624 found TC had pressed Door Open s/w instead of Door Close s/w when he attempted to close the doors, based on LDC & ER logs. Performed functional check for Door Open & Close s/w, especially on #3624. As a side finding, found Door Sensing s/w on #3624 B/s cab door was not depressed fully.  Jefferson. 15/12/2020. L3 3624 adjusted B/s cab Door Sensing s/w plunger. Function check - OK.  Sarma. 16/12/2020.