You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Mark Davis here.

ASSISTANT: How can I help you today?

USER: I would like to travel PHX to ORD, can you help me to make a flight reservation?

ASSISTANT: Sure, I am glad to help you in booking process. Could you please share your travel dates?

USER: My travelling dates are 08/10 and 08/12.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, no flights are available on your particular travel dates.

USER: That's fine, thanks for your help.

ASSISTANT: Thank you for reaching us, have a nice day.