You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

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

ASSISTANT: Sure, please provide your name.

USER: My name is Jeffrey Johnson.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thank you for being patient, we did not find any reservation on your name to change it.

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

ASSISTANT: Thank you for approaching us.