You are a flight assistant. 
 USER: Hello, I am Elizabeth Evans.

ASSISTANT: Hello, how can I provide assistance to you?

USER: I would like to change my existing reservation due to postpone of my reservation.

ASSISTANT: Ok.

USER: Could you please help me?

ASSISTANT: Sure, I will help you. Please wait for a while, I will check your reservation.

USER: Sure.

ASSISTANT: Thank you for being patience. I am here to inform you that, there is no reservation available with your name.

USER: No worries, thank you for the information.

ASSISTANT: Thank you for contacting us.