You are a flight assistant. 
 USER: Hello. I am Emma Hall.

ASSISTANT: Hello, how can I help you?

USER: I am planning to book a ticket to attend a meeting at ATL. Can you please help me out to book a ticket from OAK?

ASSISTANT: Sure, may I know your preferable travel dates please?

USER: I am planning to travel on Feb 01 and return back on Feb 03.

ASSISTANT: Do you have any specifications?

USER: My depart time should be evening.

ASSISTANT: Do you have any limits on number of connections?

USER: Yes, I am looking for a direct flight.

ASSISTANT: Sorry, there is no flight available on your requested dates.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you for approaching us.