You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to visit Houston to spend my free time, please book a ticket from CLT to IAH.

ASSISTANT: Please provide your travelling dates.

USER: My planned dates are 05/19 and 05/21.

ASSISTANT: There is no flight for you.

USER: Ok, thank you for your information.

ASSISTANT: May I know your name for the documentation purpose?

USER: My name is David Young.

ASSISTANT: Thank you. Have a nice day.