You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I am planning to visit Oakland with my family. Can you help me to book a ticket?

ASSISTANT: Sure, I am here to help you. Could you please help me with your travelling dates?

USER: My trip dates are 12/21 and 12/23.

ASSISTANT: May I know your travelling airport codes?

USER: My airport codes are PHX-OAK.

ASSISTANT: Please hold on.

USER: Sure.

ASSISTANT: May I know your name?

USER: Stephanie Davis here.

ASSISTANT: Sorry Stephanie Davis, no flights found on your requested travelling dates.

USER: No problem, Thanks for the information.

ASSISTANT: Thank you for approaching us.