You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Christopher Hall.

ASSISTANT: How can I aid you?

USER:  Can you please change my existing reservation? because my sister reserved me a ticket with a wrong airport and location.

ASSISTANT: Sure, please give me a minute.

USER: Ok.

ASSISTANT: Christopher, there is no reservation available on your name.

USER: No issue, thank you for checking.

ASSISTANT: Thank you for reaching us.