You want to change/update password for a local admin user for ProxySG/ASG
To change a local administrator console password in the Management Console:
Note : If you are using JAVA launcher for Management Console then you will need to close launcher and open again. If you are using web browser for Management console then you need to logout and log back in with new password.
If you want to reset local admin user password and username please check this article : TECH253143