You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Can you aid me to book a ticket from IAH to DCA?

ASSISTANT: May I know your travelling dates?

USER: My travel dates are May 14 and May 16 respectively.

ASSISTANT: On which name shall I reserve flight ticket?

USER: Please reserve the ticket in the name of Andrew Moore.

ASSISTANT: Do you need any connecting flight?

USER: I prefer for direct flight.

ASSISTANT: May I know your other specifications?

USER: I would like to depart for evening flight.

ASSISTANT: Sorry, there are no flight services available on your route due to bad weather forecast.

USER: No issue. Thank you.

ASSISTANT: Thank you for reaching our service.