You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Daniel Evans, want to travel from LAS to IAD. Please help me in booking my ticket.

ASSISTANT: Sure, on which dates you are planning to travel?

USER: Sure, my trip dates are from 06/24 to 06/26.

ASSISTANT: Do you have any other requirements?

USER: My return time will be in the evening and I need a connecting flight.

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Thank you for waiting. Sorry, we regret to inform you that there is no flight available as per your request.

USER: It's ok, thank you for your help.

ASSISTANT: Most welcome.