You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Mark Miller.

ASSISTANT: How may I help you today?

USER: I need to amend my reservation, can you help me out?

ASSISTANT: Sure, I am here to help you with that.

USER: Thank you.

ASSISTANT: Please wait a moment.

USER: Sure.

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

USER: That's ok, not an issue. Thank you for your information.

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