You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: This is Kevin Nelson.

ASSISTANT: Ok.

USER: I am an artist and would like to visit arts festival, which is going to be held in Phoenix. Would you please assist me in booking a flight ticket from Houston?

ASSISTANT: Sure, I am here to help you. When you are willing to travel?

USER: I am willing to travel on 05/03 and return on 05/05.

ASSISTANT: May I know your airport codes please?

USER: My airport codes are from TX-HOU to AZ-PHX.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thanks for waiting. Sorry, there are no flights found with your specifications.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.