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.

ASSISTANT: Sure, may I know your name to check for the previous reservation?

USER: I am Brain Rodriguez.

ASSISTANT: Please allow me a moment to check for the reservation status.

USER: Sure.

ASSISTANT: Brain Rodriguez, there is no reservation found under your name.

USER: No worries, thank you for the information.

ASSISTANT: Thank you for contacting us.