You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Stephanie Evans.

ASSISTANT: How can I assist you?

USER: I am planning to change an existing reservation, due to health issue.

ASSISTANT: Ok.

USER: Can you please change my reservation?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please, wait a minute.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found on your name.

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

ASSISTANT: Thank you for availing us.