You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: My name is Shirley Nelson. I just need your help in changing my existing reservation details.

ASSISTANT: Sure, I will help you.

USER: Thanks.

ASSISTANT: There is no reservation on your name in our database.

USER: That's ok, thank you for the information.

ASSISTANT: Thank you for choosing us.