Response_type=token in auth0 custom social login

 in my domain authorization url i am getting response_type=code .. from where we can change it to token

after authetnication redirecting to callback url with token but it throws error invalid_request .. and seems it causes due to response_type=code

so anyone from where we can update response_type=token

i am getting these parameters in authorization url request

'response_type' => 'code',
  'login_hint' => NULL,
  'prompt' => 'login',
  'redirect_uri' => 'https://iuncta-test.us.auth0.com/login/callback',
  'scope' => 'openid',
  'state' => 'yjVNWnIulCUS7RR-l1ifQMtrYjwGwnMg',
  'client_id' => 'test_id',