You are a flight assistant. 
 USER: Hi. Thomas Johnson here.

ASSISTANT: Hello, how can I guide you for today?

USER: I would like to book a ticket to Chicago to meet my childhood friend, can you please help me in booking a ticket?

ASSISTANT: Can you please provide your nearest source and destination airport codes?

USER: My nearest airport code is PHX and destination airport code is ORD.

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: The travelling dates are from 07/31 to 08/02.

ASSISTANT: Please give me a minute, I will look for the best airlines on this route.

USER: Ok.

ASSISTANT: Sorry, there is no flight available on your requested dates.

USER: That's ok, I will try alternate way to complete my trip.

ASSISTANT: Ok, thank you for reaching us.

USER: Most welcome.