You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: My name is Paul Walker. I want to change my existing reservation due to my sports event got postponed.

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, There is no reservation found on your name.

USER: Ok, No problem. Thanks for the information.

ASSISTANT: Thank you for contacting us.