You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: I want to change my reservation due to health problem, can you help me?

ASSISTANT: Sure, I will help you to change your reservation.

USER: Thank you.

ASSISTANT: Ok, may I know your name?

USER: Myself Steven Baker.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change your reservation.

USER: No problem, thanks for checking.

ASSISTANT: Welcome. Have a nice day.