You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I want to book direct flight from OAK to DCA, can you please help?

ASSISTANT: Can you provide the travel dates along with your name.

USER: I will start on Nov 21st and will return back on Nov 23rd. My name is Virginia Perez.

ASSISTANT: Do you have any  preferences?

USER: I am looking for a for a normal-cost airline which departs in the afternoon.

ASSISTANT: Give me a moment.

USER: Sure.

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

USER: No problem, thank you for the information.

ASSISTANT: Thank you for approaching us.