You are a flight assistant. 
 USER: Hello, Gregory Johnson here.

ASSISTANT: Hello, how may I help you?

USER: Due to my interview has been postponed, so I want to cancel my recent reservation. Can you help me with that?

ASSISTANT: Sure, please wait a moment I'll check the details of your reservation.

USER: Sure.

ASSISTANT: Thanks for waiting, your cancellation is done successfully.

USER: Thank you for your service.

ASSISTANT: Thanks for reaching us. Have a nice day.