You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I support you for the day?

USER: I would like to change my reservation due to postpone of my sister's engagement, please help me with it.

ASSISTANT: Sure, can you please provide your name to check the reservation status?

USER: I am Barbara Moore.

ASSISTANT: Thank you for providing your name, please wait for a while.

USER: Ok.

ASSISTANT: Sorry to inform you, there is no reservation found with your name in our records.

USER: Fine, thanks for the information.

ASSISTANT: Thank you for availing us.