You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Please book a ticket from Oakland, OAK to go for Film festival. Can you please book a ticket on Mar 10?

ASSISTANT: Sure, may I know your return date?

USER: I want to return on Mar 12.

ASSISTANT: Let me know your destination point.

USER: My destination is Washington, IAD.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: May I know your other specifications?

USER: My depart time is evening.

ASSISTANT: Wait a minute.

USER: Ok.

ASSISTANT: There are no flights available on your requested dates.

USER: Ok, no issues.

ASSISTANT: May I know your name for documentation purpose?

USER: I am Edward Johnson. Thank you.

ASSISTANT: Thank you for reaching us.