Here SYSADMIN is used as an example.

1.  Use FNDLOAD to download user SYSADMIN from your instance:

   FNDLOAD apps/<apps password> 0 Y DOWNLOAD $FND_TOP/patch/115/import/afscursp.lct SYSADMIN.ldt FND_USER USER_NAME=SYSADMIN

2.  Modify the ldt file (SYSADMIN.ldt for the example above).  Change the line <BEGIN FND_USER "SYSADMIN"> to <BEGIN FND_USER "SYSADMINDUP">

3.  Use FNDLOAD to upload new user to your instance:

FNDLOAD apps/apps 0 Y UPLOAD $FND_TOP/patch/115/import/afscursp.lct SYSADMIN.ldt FND_USER USER_NAME=SYSADMIN01

4.  Change the password of the new user from application