You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am David Jones. I want to attend my family meeting at BOS, can you please help me to book a ticket from IAD?

ASSISTANT: Sure, I am here to help.

USER: Thank you.

ASSISTANT: Please share me your travel dates to proceed further.

USER: I have planned to travel on 03/09 and 03/11.

ASSISTANT: Do you prefer connections between your journey?

USER: I flexible with any flight.

ASSISTANT: We have a flight from UA airline, flight number 1005 and the price 100. Shall I proceed with the booking?

USER: If the flight is leave at evening you can proceed.

ASSISTANT: It is an afternoon flight.

USER: Sorry, I want evening flight. Don't proceed for booking.

ASSISTANT: Sorry no flights available in the evening.

USER: Ok, don't proceed.

ASSISTANT: Ok.

USER: Thank you.

ASSISTANT: Thank you.