You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Charles Campbell.

ASSISTANT: How can I assist you?

USER: I need to attend a business meeting in Houston.Can you book a ticket from DFW to HOU? The connection limit is 1.

ASSISTANT: May I know your travelling dates?

USER: The departure is on 06/13 and return is on 06/15.

ASSISTANT: Sorry, there is no flight available at your request.

USER: That's really sad.

ASSISTANT: Thank you for reaching us.

USER: Anyways, thank you for your help.

ASSISTANT: You are welcome.