You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: Can you please help me to book a flight from DTW to OAK?

ASSISTANT: Please provide me your trip dates.

USER: My travel dates are Feb 19th and 21st.

ASSISTANT: Do you need any connection limit?

USER: I am fine with a connecting flight.

ASSISTANT: Can I know your preferable timings?

USER: I don't have any preference.

ASSISTANT: May I know your name for reservation?

USER: My name is Laura Thomas.

ASSISTANT: There are no flights available on your routes.

USER: No problem, thank you.

ASSISTANT: Thank you for opting us.