You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Nicole Roberts here.

ASSISTANT: How may I help you today?

USER: I want to travel from IAD to IAH for attending a Seminar. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I can help you with that. May I know your preferable travel dates please?

USER: My travelling dates are from 04/24 to 04/26.

ASSISTANT: Ok, please wait for a while.

USER: Ok, I will wait.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us.