You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you at this moment?

USER: Owing to an emergency I had to request for this change reservation.

ASSISTANT: Sure, I am glad to help you with that. May I know your name?

USER: My name is Emily Jones.

ASSISTANT: I have found the reservation. May I know your airport codes?

USER: Airport codes LAS and DEN.

ASSISTANT: Ok, can I know your planned trip dates?

USER: Trip dates are from Jul, 30 till Aug, 1.

ASSISTANT: Do you have any other requirements?

USER: I would like to return in the afternoon time.

ASSISTANT: May I know your connection limit?

USER: I prefer connecting flight.

ASSISTANT: Do you have any other specifications?

USER: I prefer business class ticket.

ASSISTANT: Sorry to say that, there are no flight's available based on your journey details.

USER: Thank you.

ASSISTANT: Thank you for reaching us.