You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Benjamin Robinson, I want to go to DFW with my friends to celebrate Christmas. Can you book our tickets from PHX?

ASSISTANT: Can you please tell your travelling dates?

USER: Our travelling dates are from 12/24 to 12/26.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there are no flights available with your requested details.

USER: That's fine, thank you for checking.

ASSISTANT: Thank you and have a nice day.