You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Paul Wilson. I need to alter my reservation, as my exam scheduled has been postponed. Could you help me in changing my existing reservation?

ASSISTANT: Sure, please wait a moment I will check and let you know.

USER: Ok.

ASSISTANT: Sorry, we did not found any reservation on your name.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your service.