You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Please change my existing reservation due to some health issues?

ASSISTANT: Sure, we are here to help you. Can I have your name to proceed?

USER: Sure, I am Donald Moore.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, sorry no reservation found on your name.

USER: Ok, not an issue. Thank you for choosing us.

ASSISTANT: Thank you for availing us.