You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: Could you please book a flight ticket from OAK to PHL?

ASSISTANT: Please provide your travelling dates?

USER: My travelling dates are Feb 01 and Feb 03.

ASSISTANT: Do you prefer connecting flight?

USER: Yes, I prefer a connecting flight.

ASSISTANT: Is there any specification?

USER: I want to return in the afternoon.

ASSISTANT: Can I know your name?

USER: I am Lisa Martin.

ASSISTANT: Sorry, there are no flights for your travelling dates.

USER: No problem, thank you.

ASSISTANT: Thank you.