You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Can you please help me to book a flight from AUS to IAH?

ASSISTANT: May I know your travel dates?

USER: I want to depart on Sept 21 and need to return on Sept 23.

ASSISTANT: Do you prefer connecting flight?

USER: I am looking for a flight with single connection.

ASSISTANT: Do you have any other specifications?

USER: My return time must be in the afternoon.

ASSISTANT: May I know your good name?

USER: I am Nancy Carter.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.