You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

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

ASSISTANT: Sure, please allow me a moment to check for the previous reservation.

USER: Sure, I will wait.

ASSISTANT: Angela, there is no reservation found under your name.

USER: That's fine.

ASSISTANT: Thank you for reaching us, have a great day.

USER: Thank you for your service.