You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How can I serve you today?

USER: I want to meet my childhood friend in Washington, DC - IAD, will you help me in flight booking?

ASSISTANT: Sure, may I know your good name?

USER: My origin source from Oakland, CA - OAK, my name is Katherine Garcia.

ASSISTANT: On what dates would you like to travel to Washington?

USER: My travelling dates from 09/09 to 09/11.

ASSISTANT: Please wait for while.

USER: Sure.

ASSISTANT: Thanks or waiting, sorry there is no any flight found on your requirement.

USER: Ok, no problem, thank you, for your service.

ASSISTANT: Thank you, have a great day.