You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Debra Wilson.

ASSISTANT: How can I assist you today?

USER: I want to book a ticket from HOU to IAH to meet my friends in Houston.

ASSISTANT: Sure, I can help you in booking flight ticket. Could please let me know your travel dates for booking flight ticket?

USER: I am departing on 09/14 and return on 09/16.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there is no flights available as per your requested dates.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for contacting us, have a good day.