You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Jerry Campbell.

ASSISTANT: How may I help you?

USER: Me and my wife planned to celebrate our tenth anniversary in Washington.Can you please book a ticket on 01/18 and 01/20?

ASSISTANT: Wait, give me a minute. May I know your airport codes?

USER: My airport codes are PHX and DCA.

ASSISTANT: Sorry to say that there is no flight found.

USER: That's ok.

ASSISTANT: Thank you for contacting us.

USER: Thank you for your time.