You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I am Matthew Brown. I am planning to book a ticket to attend a meeting at DFW. Can you please help me out to book a ticket from DCA?

ASSISTANT: Sure Brown, can you please help me with your planned dates of travel?

USER: I would like to travel on Feb 09 and return back on Feb 11.

ASSISTANT: May I know your class preference please?

USER: I am ok with any class.

ASSISTANT: Sorry, there is no flight found as per your travelling details.

USER: That's fine, thank you for your service.

ASSISTANT: You are welcome.