You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in changing my existing reservation, as my exam got postponed.

ASSISTANT: May I know your name please?

USER: My name is Sandra Anderson.

ASSISTANT: Please wait a while.

USER: Ok.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for opting us.