You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: My name is Jeffrey Gonzalez. I want to change my existing reservation due to health issues.

ASSISTANT: Sure, please give me a minute.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no reservation found with your name.

USER: No problem, thanks for your service.

ASSISTANT: Have a good day.