You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: My name is Anna Robinson.

ASSISTANT: Yes, Anna.

USER: Due to some problems issuing in my destination location, so I want to do some changes in my existing reservation. Can you help me for that?

ASSISTANT: Sure, I will assist you in modifying your reservation.

USER: Fine, thank you.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Sorry, I did not find any reservation on your name.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, have a nice day.