Traccar Client

Is there some trick to getting the traccar client (android) to work?  I've installed it on my phone for a test because a customer was wanting to use it and with the proper IP:PORT in the URL field the client on the mobile loads but in the status always shows a "Send Failed" message.  From my Wialon web interface and from CMS I see the client did connect once but then for some reason it started failing?  It continued failing and never Sent another position update. 

I have tried the URL with a SSL and without (http vs https)  Same problem "Send Failed" in the status messages and no connection or messages in Wialon.