You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you today?

USER: Can you please help me with changing my recent reservation?

ASSISTANT: Yes, I am here to help you. May I know your name please?

USER: My name is William Miller.

ASSISTANT: Ok, wait a minute please.

USER: Ok.

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

USER: That's ok.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you.