You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I guide you now?

USER: Can you please help me with changing my existing reservation?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: For changing your reservation, we need to know your name for checking your reservation status. Can you please forward me your name?

USER: I am Anna Robinson.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, we have not found any reservation on your name in our records.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.