You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am Frank Hall, want to travel from PHX on 12/01. Please help me in booking my ticket.

ASSISTANT: Can I know your return travel details?

USER: Yes, my destination airport code is IAD and want to return on 12/03.

ASSISTANT: Sorry Frank, there are no flights available on your requested dates.

USER: It's ok, not an issue. Anyway, thank you for your help.

ASSISTANT: You are welcome.