You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I would like to change my reservation due to some health issues, will you help me?

ASSISTANT: Sure, may I know your good name?

USER: Sure, my name is John Thomas.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: It's Ok, thanks for your support.

ASSISTANT: Thank you for reaching us.