You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, How can I help you?

USER: My name is Carolyn Evans. Please book a ticket from Houston, TX-HOU to Houston, TX-IAH, for festival celebration.

ASSISTANT: Sure, May I know the travel dates?

USER: I will depart on 09/14 and will return by 09/16.

ASSISTANT: Please give a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Thanks for the help.

ASSISTANT: Thank you for opting us.