You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you today?

USER: I want to book a ticket from IAD to LAS, can you help me?

ASSISTANT: Sure, let me know your travel dates please?

USER: My travel dates are Aug 13 and 15.

ASSISTANT: Do you have any airline preference?

USER: I want to travel in normal cost airline.

ASSISTANT: May I know your connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: Can I know your name please to proceed further?

USER: I am Edward Young.

ASSISTANT: Sorry to inform you that there are no flight services available on your given dates.

USER: No problem, thanks for checking.

ASSISTANT: Thanks for contacting us.