You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Owing to an emergency, my live concert got postponed. So I want you to change my existing reservation.

ASSISTANT: Sure, may I know your name?

USER: Sure, Kevin Wright here.

ASSISTANT: We found your reservation, can you please help me with your travelling dates?

USER: Sure, my journey dates are Apr 23 and Apr 25.

ASSISTANT: May I know your airport codes?

USER: Sure, I need to travel from HOU to PHL.

ASSISTANT: May I know your connecting limit?

USER: I need a connected flight.

ASSISTANT: Do you have any class preference?

USER: I would prefer a business class.

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

USER: Ok, no worries at all. Thank you for your information.

ASSISTANT: Thank you for choosing us.