You are a flight assistant. 
 USER: Hello, I am Shirley Brown.

ASSISTANT: Hello. How can I support you?

USER: Can you please book a flight on 11/07?

ASSISTANT: Sure. Do you have any connection limit?

USER: No, I need a direct flight.

ASSISTANT: Let me know your airport codes.

USER: Ok. I would like to go to Dallas, DFW to meet my childhood friend. I will start from Washington, DCA.

ASSISTANT: May I know your return date?

USER: I need to return on 11/09.

ASSISTANT: Please, wait.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no direct flight available with your given requirements.

USER: Ok. Thank you.

ASSISTANT: Thank you.