Unable to merge dex Android

Last time I build successfully but after adding the number of pages I am unable to build, I did search for that error a lot but nothing works for me.For example, added and removed the platform, ionic cordova clean , ionic cordova build etc…

Following Error facing by running-- ionic cordova build android

  • What went wrong:
    Execution failed for task ‘:app:transformDexArchiveWithExternalLibsDexMergerForD

java.lang.RuntimeException: java.lang.RuntimeException: com.android.builder.de
xing.DexArchiveMergerException: Unable to merge dex

  • Try:
    Run with --stacktrace option to get the stack trace. Run with --info or --debug
    option to get more log output.

  • Get more help at https://help.gradle.org


IOnic Info:

cli packages: (C:\Users\ITSERV\AppData\Roaming\npm\node_modules)

@ionic/cli-utils  : 1.19.2
ionic (Ionic CLI) : 3.20.0

global packages:

cordova (Cordova CLI) : 8.0.0

local packages:

@ionic/app-scripts : 3.1.8
Cordova Platforms  : android 7.0.0
Ionic Framework    : ionic-angular 3.9.2


Node : v6.11.2
npm  : 3.10.10
OS   : Windows 7

Thanks in advance!