You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I render you today?

USER: Can you please book a flight ticket with the name of Nicholas Lewis?

ASSISTANT: Sure, I am here to help you out. Please provide me your location airport codes.

USER: My airport codes are, Phoenix, PHX to Detroit, DTW.

ASSISTANT: May I know your planned trip dates?

USER: I want to start my journey on 10/12 and need to catch return flight on 10/14.

ASSISTANT: I regret to inform to that, there is no flight in your route with your desired travel dates. Sorry for inconvenience caused.

USER: Ok, no problem at all. Thank you for your information.

ASSISTANT: Thank you for reaching us.