You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I would like to change my reservation due to some health issues, can you please help me out with that?

ASSISTANT: Sure, I am glad to help you with that. Can you please share me your name?

USER: Thank you. Myself Lisa Williams.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no active reservation found on your name in our database.

USER: That's ok, no problem. Anyway thank you for checking out.

ASSISTANT: Thank you for opting us, have a nice day.