You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you today?

USER: I need to book a flight ticket from IAD to AUS, can you help me in booking a flight ticket?

ASSISTANT: Sure, when are you planning to start and return on?

USER: Sure, my scheduled dates are Mar 31 and Apr 2.

ASSISTANT: Can I know your connection limit?

USER: I prefer maximum one connection.

ASSISTANT: Do you have any other specifications?

USER: I would prefer depart time at evening.

ASSISTANT: Can I know your good name?

USER: Sure, Andrew Williams here.

ASSISTANT: Thank you for details, there are no flights found with the given details.

USER: Ok, no issues. Thank you for your assistance.

ASSISTANT: Thank you for contacting us.