You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I just want to change an existing reservation due to my plans to meet my former colleague got post pone. Can you please check the reservation by this name Christoper Carter?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, there was no reservation found with your name.

USER: Ok, not an issue. Thanks for your information.

ASSISTANT: Thank you for choosing us.