You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Can you help me to book a direct flight ticket?

ASSISTANT: Sure, may I know your travel dates?

USER: My travel dates are May 04 and May 06.

ASSISTANT: Please share me your airport codes.

USER: My airport codes are AUS and OAK.

ASSISTANT: Please share me your name.

USER: I am Daniel Allen.

ASSISTANT: Do you have any specifications?

USER: I would like to return back in the evening time.

ASSISTANT: Sorry, there is no flight at this moment.

USER: No problem, thank you for the information.

ASSISTANT: Thank you.