You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am extending my food business in other cities also, so to start new branch in Denver, I need to go there. So, book a flight on 06/16.

ASSISTANT: Sure. May I know your journey points?

USER: Sure. I will depart from Houston, HOU. I need a connecting flight between my journey. And I have to open a new branch in Denver, DEN.

ASSISTANT: Can I know your return date?

USER: Yes, I may return on 06/18.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: We did not find any connecting flight matching your criterion. Can you please provide your name?

USER: Ok, Thanks for sharing information. I am Andrew Jones.

ASSISTANT: Thank you for choosing us.