You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,. How may I support you?

USER: My friend birthday party place has been changed to Detroit. Can you please change my existing reservation?

ASSISTANT: May I have your good name please?

USER: I am Donna Walker.

ASSISTANT: Please hold on a moment.

USER: Sure.

ASSISTANT: We are very sorry to inform you that there is no reservation found on your given name.

USER: Ok, not a problem at all.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your quick response.