Not able to configure static IP in two lan card in my desktop

[Roan Rai]

cannot set static ip by editor or in terminal. Though the gui network connection works for inbuilt LAN card, but cannot set statip IP for external LAN card.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: lxterminal 0.2.0-1
ProcVersionSignature: Ubuntu 4.4.0-34.53-generic 4.4.15
Uname: Linux 4.4.0-34-generic i686
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: i386
CurrentDesktop: LXDE
Date: Mon Aug 29 11:22:00 2016
ExecutablePath: /usr/bin/lxterminal
InstallationDate: Installed on 2016-08-25 (4 days ago)
InstallationMedia: Lubuntu 14.04 LTS "Trusty Tahr" - Release i386 (20140416.2)
ProcEnviron:
 LANGUAGE=en_IN:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_IN
 SHELL=/bin/bash
SourcePackage: lxterminal
UpgradeStatus: Upgraded to xenial on 2016-08-25 (3 days ago)