You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, hoe can I amend you today?

USER: My name is Rachel Carter, I want to change my existing reservation due to postpone of my interview.

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting. There is no reservation found with your given details.

USER: Not an issue, thank you.

ASSISTANT: Thank you for choosing us.