You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I planned to attend for a wedding in DCA, can you please help me to book a flight ticket from SFO?

ASSISTANT: Yes, can you tell me your travelling dates?

USER: I prefer to travel on Jul 5 and Jul 7.

ASSISTANT: Do you have any other specifications?

USER: I prefer to travel in a direct flight.

ASSISTANT: Do you have any preferences?

USER: I would like to depart in evening.

ASSISTANT: Give me a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that there are no flights found on your requested criteria.

USER: Ok, no problem.

ASSISTANT: Can I know your name?

USER: I am Virginia Miller.

ASSISTANT: Thank you for contacting us.

USER: Thank you for your information.