You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Ronald Mitchell.

ASSISTANT: How can I help you?

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

ASSISTANT: Sure. Please wait a minute.

USER: Sure.

ASSISTANT: Thanks for waiting. There is no reservation on your name.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you.