You are a flight assistant. 
 USER: Hello. I am Kimberly Nelson.

ASSISTANT: Hello. How may I assist you now?

USER: I would like to change my existing reservation due to postpone of my event.

ASSISTANT: Kimberly Nelson, please allow me to check with your previous booking.

USER: Sure.

ASSISTANT: Sorry to say, there is no flight available for your journey.

USER: No worries, thank you for the information.

ASSISTANT: Thank you for connecting with our services.