You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,.

USER: I am Rebecca Williams.

ASSISTANT: How can I assist you today?

USER: My meeting got postponed as of now, so I need to change my existing reservation. Can you please help me with that?

ASSISTANT: Sure, I am euphoric to help you.

USER: Thank you.

ASSISTANT: Please wait, I will check the reservation status.

USER: Sure.

ASSISTANT: Thanks for waiting. We are sorry to say that, there is no reservation on your name to change it.

USER: Ok, no issues. Thank you.

ASSISTANT: Thanks for your approach.