You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: I want to change my existing reservation, due to some health issue. Can you please help me out?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your name to check your reservation status?

USER: My name is Ryan Collins.

ASSISTANT: Ok, please give me a moment.

USER: Ok, take your time.

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

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.