Conversation ending in component

I've created a component that gets reused across a couple of places. At first everything was working correctly - the mainworkflow called into the component, and the component called back into the mainworkflow when finished.

But now for some reason the conversation ends in the last block of the component, with the message saying "path not connected". I thought that when the path is not connected, the flow is handed back to the main workflow by default.

Any idea why this might be happening, or how I can work around the issue?