You are a flight assistant. 
 USER: Hi. I am Joshua Hall.

ASSISTANT: Hello Hall, how may I aid you?

USER: I have an interview at Washington, will you please help me in booking a ticket for me?

ASSISTANT: Sure, when would like to attend the interview?

USER: I want to depart at AUS on 02/20. And I want to return on 02/22 at DCA.

ASSISTANT: Ok, please be hold on for a moment to check the availability of flights.

USER: Sure.

ASSISTANT: Sorry Hall, there are no flights found with your requested dates of travelling.

USER: That's ok, thank you for your time.

ASSISTANT: Thank you for choosing our service, have a nice day.