You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to change my existing reservation due to postpone of my event. Could you please help me?

ASSISTANT: Sure, will you mention your name please?

USER: I am Shirley Wright.

ASSISTANT: There is no reservation found under your name. Thanks for reaching us, have a great day.

USER: No worries, thank you for the information.