You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Janet Davis.

ASSISTANT: How may I assit you?

USER: I want to change my existing reservation, can you help me in that?

ASSISTANT: Sure, I am here to help you out.

USER: Thank you.

ASSISTANT: Janet Davis, we regret to inform you that there is no reservation found on your name in our records.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for choosing us.