You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you at this moment?

USER: As my meeting got postponed, can you please help me in changing my existing reservation ?

ASSISTANT: Sure, I will help you. Please wait for a moment. May I know your name?

USER: My name is Alexander Hernandez.

ASSISTANT: Sorry, there is no reservation available with your name.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: You are welcome. Thank you for reaching us, have a nice day.