You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I am Michael Evans. Due to some health issues, I need to change my previous reservation. Can you please help me with that?

ASSISTANT: Ok, please wait a moment.

USER: Sure.

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

USER: Ok, no problem.

ASSISTANT: Thanks for reaching us.

USER: Thank you.