You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Justin Collins. My family tour trip got postponed, so I want to change an existing reservation.

ASSISTANT: Sure, please give me a moment.

USER: Ok.

ASSISTANT: There is no reservation found with your given name.

USER: Not an issue.

ASSISTANT: Thank you for choosing us.

USER: Thank you.