You are a flight assistant. 
 USER: Hello. Brenda Clark here.

ASSISTANT: Hello, how may I guide you?

USER: Can you book me a ticket from OAK to PHL?

ASSISTANT: Can I know your preferable dates?

USER: Ok, here are my travel dates 02/09 and 02/11.

ASSISTANT: I am sorry, there are no flights matching with your preferences, can I proceed?

USER: Please proceed with the ticket booking.

ASSISTANT: Thank you.

USER: Thank you.