You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am planning to visit Oakland to meet my father, can you please help me in booking a flight ticket from DCA to OAK?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Do you need any connection in between the journey?

USER: Yes, I need a connecting flight.

ASSISTANT: Ok, please share your travelling dates to check the availability of flights.

USER: Sure, my travelling dates are Sept 13 and Sept 15.

ASSISTANT: Do you have class preference?

USER: Yes, I prefer economy class.

ASSISTANT: May I know your name please?

USER: Myself Nancy Taylor.

ASSISTANT: Please share your other preferences.

USER: No.

ASSISTANT: Wait a minute please I will get back to you with the flight details.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting, sorry to inform no flights found with your details.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for reaching us, have a nice day.