Firebase Login Error (FirebaseNetworkException)

[박인환]

mCustomToken = receiveToken;

mAuth.signInWithCustomToken(mCustomToken).addOnCompleteListener(new OnCompleteListener<AuthResult>() {

    @Override
    public void onComplete(@NonNull Task<AuthResult> task) {
        if(!task.isSuccessful()) {
            Log.w(LOG_TAG, "signInWithCredential", task.getException());
        }
        FirebaseUser user = task.getResult().getUser();

        if (user != null) {
            // User is signed in
            Log.d(TAG, "onAuthStateChanged:signed_in1:" + user.getUid() + " / " + user_email + " / " + user_name + " / " + user_profile_image );

            //insert shared preference
            SharedPreferences pref = getSharedPreferences("bebr_user", MODE_PRIVATE);
            SharedPreferences.Editor editor = pref.edit();
            editor.putString("user_custno", user.getUid().replaceAll("bebranch#",""));
            editor.putString("user_email", user_email);
            editor.putString("user_name", user_name);
            editor.putString("user_profile_image", user_profile_image);
            editor.commit();

            Intent intent = new Intent(getApplicationContext(), MainActivity.class);
            startActivity(intent);

            showProgress(false);
            finish();

        } else {
            // User is signed out
            Log.d(TAG, "onAuthStateChanged:signed_out1");
        }
    }
});

getting error on FirebaseUser user = task.getResult().getUser();

com.google.firebase.FirebaseNetworkException: A network error (such as timeout, interrupted connection or unreachable host) has occurred.

                                                                                     at com.google.android.gms.internal.zzahe.zzfc(Unknown Source)

                                                                                     at com.google.android.gms.internal.zzahb$zzg.zza(Unknown Source)

                                                                                     at com.google.android.gms.internal.zzahm.zzfd(Unknown Source)

                                                                                     at com.google.android.gms.internal.zzahm$zza.onFailure(Unknown Source)

                                                                                     at com.google.android.gms.internal.zzahh$zza.onTransact(Unknown Source)

                                                                                     at android.os.Binder.execTransact(Binder.java:453)

weird thing is some device is working and some device is gettting error

I'm very sure my every device well connected to internet,  quiet sure internet connection is not a problem