Execution failed for task ':app:processDebugGoogleServices'. in IONIC 4

Ionic Framework Ionic Angular
1

I have to do phone authentication in my project.
I follow the instruction from: https://ionicframework.com/docs/native/firebase-authentication
google-services.json file is already added in root of the project.

.ts

createAccount() {
  this.firebaseAuthentication.verifyPhoneNumber("1234567890",3000)
  .then(function(verificationId) {
    alert(verificationId);
    // pass verificationId to signInWithVerificationId
  })
  .catch((error: any) => alert(error));

    // this.router.navigateByUrl('/profile');
  }

When I run it in emulator I got error.

  • What went wrong: Execution failed for task ‘:app:processDebugGoogleServices’.

File google-services.json is missing. The Google Services Plugin cannot function without it. Searched Location:
E:\Unnati\WorkSpace\remed\platforms\android\app\src\nullnull\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\debug\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\nullnullDebug\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\nullnull\debug\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\debug\nullnull\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\google-services.json

  • Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
  • Get more help at https://help.gradle.org

BUILD FAILED in 2s 20 actionable tasks: 1 executed, 19 up-to-date E:\Unnati\WorkSpace\remed\platforms\android\gradlew: Command failed with exit code 1 Error output: FAILURE: Build failed with an exception.

  • What went wrong: Execution failed for task ‘:app:processDebugGoogleServices’.

File google-services.json is missing. The Google Services Plugin cannot function without it. Searched Location:
E:\Unnati\WorkSpace\remed\platforms\android\app\src\nullnull\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\debug\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\nullnullDebug\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\nullnull\debug\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\src\debug\nullnull\google-services.json E:\Unnati\WorkSpace\remed\platforms\android\app\google-services.json

  • Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
  • Get more help at https://help.gradle.org

BUILD FAILED in 2s [ERROR] An error occurred while running subprocess cordova.