You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Gary Lopez.

ASSISTANT: How can I help you Lopez?

USER: I am planning to book a ticket to attend a music event at HOU. Can you please help me out to book a ticket from DCA?

ASSISTANT: Could you please tell me your trip dates?

USER: I would like to travel on 12/16 and return back 12/18.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, I will wait.

ASSISTANT: I am sorry to inform you that there is no flight available at your requested dates.

USER: That's fine.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your service.