Hi.
user
Hello. How may I serve you today?
assistant
I need to book a ticket from IAD to LAS. Could you book a ticket?
user
Sure, I am here to help you to make a flight reservation but I need your travel dates to search a flight.
assistant
Travel dates are Dec, 18 and Dec, 20.
user
May I know your depart and arrival timings?
assistant
I would like to return in the evening.
user
Please let me know if you need a connecting flight.
assistant
I need single connection flight.
user
Is there any other specifications?
assistant
I prefer business class ticket.
user
Thank you for sharing your journey details,  we are unable to provide flight in between your journey routes due to some technical up-gradation at destination airport.
assistant
Thank you.
user
May I know your name please?
assistant
My name is Paul Collins.
user
Thank you.
assistant