You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

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

ASSISTANT: Sure, I am here to help you out. Please allow me a moment to check the reservation status.

USER: Sure.

ASSISTANT: Sorry Daniel Brown, there is no reservation on your name in our database.

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

ASSISTANT: Thank you for reaching us.