You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Can you please help me to book a ticket from EWR to LAS?

ASSISTANT: Sure, could you please with your trip dates?

USER: I want to start on July 27 an return on July 29.

ASSISTANT: Do you need any connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: I would prefer business class. I would prefer normal-cost airline.

ASSISTANT: Can I know your name?

USER: Christopher Evans here.

ASSISTANT: Sorry, there are no flights available on your request.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.