Retrofit 2.0 Conditional Logic in onResponse not working - retrofit2

Question

I am trying to make a login logic using post request with retrofit, here is my code
Button btnLogin = (Button) findViewById(R.id.btn_login);
btnLogin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
showProgress(true,"Sedang login... ");
String username = inputUsername.getText().toString();
String password = inputPassword.getText().toString();
apiService.login(new LoginParam(username,password)).enqueue(new Callback<AuthResponse>() {
#Override
public void onResponse(Call<AuthResponse> call, Response<AuthResponse> response) {
if(response.isSuccessful()){
showProgress(false,null);
Editor ed = sp.edit();
ed.putString("token",response.body().getToken());
Boolean login = response.body().getLogin();
Log.d("Login",response.body().getLogin().toString());
ed.putBoolean("login",response.body().getLogin().booleanValue());
ed.putString("username",response.body().getUser().getUsername());
ed.commit();
//startActivity(new Intent(getBaseContext(), MainActivity.class));
if(!login){
TextView infologin = (TextView) findViewById(R.id.loginInfo);
infologin.setText("Username dan password salah, coba lagi");
infologin.setVisibility(View.VISIBLE);
return;
}
else{
Intent i = new Intent(getBaseContext(),MainActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP| Intent.FLAG_ACTIVITY_CLEAR_TASK);
i.putExtra("route","afterlogin");
startActivity(i);
finish();
}
}
}
#Override
public void onFailure(Call<AuthResponse> call, Throwable t) {
LoginActivity.this.showProgress(false, null);
Toast.makeText(LoginActivity.this, "Gagal koneksi ke server, periksa jaringan internet anda error: " + t.toString(), Toast.LENGTH_LONG).show();
}
});
}
});
it was working when username and password are correct, but when it was not, it only shows a loading animation, the block that handle if login is false remains inexecuted. what's going wrong?