You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I want to change my reservation as my meeting is postponed. Can you help me with that?

ASSISTANT: Sure, may I know your name for the changing process?

USER: My name is Brandon Walker.

ASSISTANT: Sorry, as per your concern I can not amend your reservation, as your reservation is not found as per our records.

USER: Ok, thank you for the information.

ASSISTANT: Welcome, thank you for reaching us.