Error: Failed to transpile program

all was good, sudden stopped working the build. with error Error: Failed to transpile program

cli packages: (/var/www/html/bh/node_modules)

    @ionic/cli-plugin-cordova       : 1.6.2
    @ionic/cli-plugin-ionic-angular : 1.4.1
    @ionic/cli-utils                : 1.7.0
    ionic (Ionic CLI)               : 3.7.0

global packages:

    Cordova CLI : 6.5.0 

local packages:

    @ionic/app-scripts : 2.1.3
    Cordova Platforms  : android 6.2.2
    Ionic Framework    : ionic-angular 3.6.0

System:

    Node : v7.5.0
    OS   : Linux 4.4
    npm  : 4.1.2

–verbose


[DEBUG] CLI flags: { interactive: true, confirm: false }
[DEBUG] { cwd: '/var/www/html/bh', local: true, binPath:
        '/usr/local/lib/node_modules/ionic/bin/ionic', libPath:
        '/var/www/html/bh/node_modules/ionic/dist/index.js' }
[DEBUG] Loading local plugin @ionic/cli-plugin-proxy
[DEBUG] Throwing PLUGIN_NOT_INSTALLED for local @ionic/cli-plugin-proxy
[DEBUG] Loading local plugin @ionic/cli-plugin-cordova
[DEBUG] Loading local plugin @ionic/cli-plugin-ionic-angular
[DEBUG] New daemon pid: 12583
[DEBUG] Getting plugin info for ionic
[DEBUG] Checking for latest plugin version of ionic@latest.
[DEBUG] Getting plugin info for @ionic/cli-plugin-cordova
[DEBUG] Checking for latest plugin version of @ionic/cli-plugin-cordova@latest.
[DEBUG] Getting plugin info for @ionic/cli-plugin-ionic-angular
[DEBUG] Checking for latest plugin version of
        @ionic/cli-plugin-ionic-angular@latest.

Hope someone can help ?

Sorry issue was because improper comment a variable in provider.