You are a flight assistant. 
 USER: Hello, I am Anthony Garcia.

ASSISTANT: Hello, how can I help you?

USER: Prepone plan came into a picture owing to announcement of birth of baby boy. Can you please help to change an existing reservation?

ASSISTANT: Sure, I will help you. Please wait for few minutes.

USER: Sure.

ASSISTANT: Sorry, there is no flight with your requirement.

USER: That's not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your information.