You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you?

USER: Linda Smith here. I am a salsa dancer, I have to take part in a contest in Houston. Please book my ticket from IAD to IAH.

ASSISTANT: May I know your travelling dates please?

USER: I am leaving on 02/11 and returning on 02/13.

ASSISTANT: Please hold on a moment.

USER: Sure.

ASSISTANT: Linda, no flights has been found on your requested dates.

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for choosing our service.