Ionic cordova run android fails

Hi,

I go the following error message with ionic cordova run android command. I think I messed up with the android env variables. Anyone knows how to fix this? Thanks!

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'android'.
> java.lang.NullPointerException (no error message)

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

BUILD FAILED

ionic info

cli packages: (/Users/J/.nvm/versions/node/v8.2.1/lib/node_modules)

    @ionic/cli-utils  : 1.10.2
    ionic (Ionic CLI) : 3.10.3

global packages:

    Cordova CLI : 6.5.0 

local packages:

    @ionic/app-scripts : 2.1.4
    Cordova Platforms  : android 6.2.3 ios 4.4.0
    Ionic Framework    : ionic-angular 3.6.1

System:

    Android SDK Tools : 24.4.1
    ios-deploy        : 1.9.2 
    ios-sim           : 6.0.0 
    Node              : v8.2.1
    npm               : 5.2.0 
    OS                : macOS Sierra
    Xcode             : Xcode 8.3.2 Build version 8E2002 

sdkmanager info:

Installed packages:=====================] 100% Computing updates...             
  Path                        | Version | Description                    | Location                    
  -------                     | ------- | -------                        | -------                     
  build-tools;25.0.2          | 25.0.2  | Android SDK Build-Tools 25.0.2 | build-tools/25.0.2/         
  build-tools;26.0.1          | 26.0.1  | Android SDK Build-Tools 26.0.1 | build-tools/26.0.1/         
  emulator                    | 26.1.4  | Android Emulator               | emulator/                   
  extras;android;m2repository | 47.0.0  | Android Support Repository     | extras/android/m2repository/
  extras;google;m2repository  | 58      | Google Repository              | extras/google/m2repository/ 
  patcher;v4                  | 1       | SDK Patch Applier v4           | patcher/v4/                 
  platform-tools              | 26.0.0  | Android SDK Platform-Tools     | platform-tools/             
  platforms;android-24        | 2       | Android SDK Platform 24        | platforms/android-24/       
  platforms;android-25        | 3       | Android SDK Platform 25        | platforms/android-25/       
  tools                       | 26.1.1  | Android SDK Tools              | tools/                    

what about removing android platform and re-add it again ?

ionic cordova platform remove android

then

ionic cordova platform add android

I have tried adding and removing platforms. thanks