You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I need your help to change an existing reservation.

ASSISTANT: Sure, I am happy to help you.Just give me a minute?

USER: Sure.

ASSISTANT: Sorry to say that there is no reservation found.

USER: That's OK. Thank you for the information.

ASSISTANT: May I know your name?

USER: My name is Scott Mitchell.

ASSISTANT: Thank you Scott for contacting us.

USER: Thank you for your help.