You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: Sharon Wright here, can you please help me in booking the ticket from DFW to LGA? As I have to attend my graduation ceremony in New York university.

ASSISTANT: Sure, can I know your preferable dates?

USER: Sure, my planned departure and return travel dates are 12/17 and 12/19.

ASSISTANT: Sorry to inform there are no flights available at your preferred location. Thank you for your help.

USER: Oh! That's ok, thank you for giving the information.