Which version is your app based on (go to the iOS Settings app, find your app, and you will find it). In addition, did you click the "Preflight" button in the content view of the portal? It's the little eyeball icon in the upper right.
Its not really an error message, just text that says "Cannot connect to 2016 Midland Metal Check your connection then tap to refresh". I've tried on a variety of connections that I know are working and it still gives this message.