You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: Will you please aid me in making an airline reservation from IAH to IAD?

ASSISTANT: Sure, may I know your planned travelling dates?

USER: My planned travelling dates are Sept 25th and Sept 27th.

ASSISTANT: For further proceeding, may I know your good name?

USER: Emma Miller.

ASSISTANT: Would you like to fly in economy class flight or business class flight?

USER: I am ok with any class.

ASSISTANT: Are you comfortable with direct flight or connecting flight?

USER: I need a direct flight.

ASSISTANT: Do you have specific time preference for journey?

USER: No.

ASSISTANT: Sorry to inform you that, there is no flight found as per your travelling details.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.