What is the sequence of events for ending a call that was spawned using RingOut?

My users will have an app that they can use to click on a client's phone number, and it will dial the physical phone sitting beside them on the desk. I'm using RingOut for this. I've never done this before so I need to know about ending the call. The RingOut API call creates a "call object". Does that call object have to be ended (deleted) by my app that started the call using the RingOut API (meaning, user has to click an "End Call" button, or is it automatically deleted by the staff member or client (or both) hanging up their physical phone? The reason I ask is because of the GET (Ringout Status) API call will fail and be marked by the RingOut system as an error on my part (404).. .and then what happens? I get punished some how? If I have to have an "End Call" button in my app, that users have to click after they physically hang up after each call.. for sure they are going to get confused and click the "End Call" button (DELETE) and again, if the call object is not there, another 404 will get generated.