You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Carol Adams. I am planning to change an existing reservation, due to health issue. Can you please change my reservation?

ASSISTANT: Sure, please wait for a moment to check your details.

USER: Sure, I will wait.

ASSISTANT: Sorry to say, no reservation found on your name.

USER: That's fine. Thank you for your service.

ASSISTANT: You are welcome.