You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Please book a ticket from ORD to PHX to attend Sports festival.

ASSISTANT: May I know your desired travel dates please?

USER: My journey dates are Oct 25 and Oct 27.

ASSISTANT: Do you have any specifications?

USER: My depart time is morning.

ASSISTANT: May I know your name please?

USER: I am Helen Evans.

ASSISTANT: Sorry to say, there is no flight on your desired travel dates.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for opting us.