You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I am Michael Jackson. Owing to an emergency, I need to change an existing reservation. Can you help me with this?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait a moment.

USER: sure.

ASSISTANT: Sorry there is no reservation on your name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you.