You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I would like to change my flight reservation as my trip got postponed, can you please help me?

ASSISTANT: Sure, may I know your name for checking with the details.

USER: My name is Catherine White.

ASSISTANT: Please wait a moment.

USER: Ok, take your time.

ASSISTANT: Sorry, there are no active reservations on your given name to change.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching our service.