You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I know your good name Please?

USER: This is Nancy Brown, and I want to change my existing reservation. Can you please help me?

ASSISTANT: Sure Nancy, could you please wait for a minute.

USER: OK.

ASSISTANT: Sorry for this inconvenience, I cannot find any reservation with your name.

USER: Thank you, for your kind information.

ASSISTANT: It was my pleasure. Have a nice day!.