You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: Could you help me in booking a flight ticket from LAS to IAH?

ASSISTANT: Sure, can you please share your journey dates?

USER: I will start on Oct 21, return on Oct 23.

ASSISTANT: May I know your connection limit please?

USER: I need a single connecting flight.

ASSISTANT: May I know your name please?

USER: My name is William Brown.

ASSISTANT: Do you have any more specifications in your journey?

USER: My depart time should be afternoon.

ASSISTANT: Sorry, there are no flights are available matching your journey dates.

USER: Not an issue, thank you.

ASSISTANT: Thank you for choosing us.