You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you now?

USER: I am planning to change my existing reservation due to sudden change of my trip dates. Can you help me with that?

ASSISTANT: Sure.

USER: Thank you.

ASSISTANT: I have to know your name to change the reservation, Will you please?

USER: I am Sandra White.

ASSISTANT: Thanks for your name. There was no reservation on your name to change.

USER: Ok , no issues.

ASSISTANT: Thank you for opting us, have a nice day.

USER: Thank you.