title: Retrofit2: ExecutorCallAdapterFactory error
body: <p>After calling API's using Retrofit 2.0, Unable to get any response and getting this error: </p>
  
  <p><strong>Failure: retrofit2.ExecutorCallAdapterFactory$ExecutorCallbackCall@5e38d31</strong></p>
  
  <p>I think this is internal retrofit error.
  Please help!</p>