You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,.

USER: I am Nancy Taylor.

ASSISTANT: How can I help you?

USER: I want to buy a car in Houston, TX - HOU. Can you please help me to book a plane ticket.

ASSISTANT: Sure, provide me with your journey dates.

USER: I want to start from Phoenix, AZ - PHX on 09/13 and return on 09/15.

ASSISTANT: OK, wait a minute.I will check with the availability and revert you.

USER: Sure.

ASSISTANT: Sorry to inform you that there is no flight available with your specification.

USER: OK, no issue. Thanks for your response.

ASSISTANT: Thank you . Have a good day.