You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Jessica Jackson.

ASSISTANT: What can I do for you?

USER: My business meeting has been postponed.So, I would like to change my existing reservation which is under my name. Can you please help me with that?

ASSISTANT: Sure.

USER: Thank you.

ASSISTANT: There is no reservation has been found on your name.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for visiting us.

USER: You are welcome.