You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I best serve you today?

USER: Can you help me to change my reservation?

ASSISTANT: Sure, I am happy to help you to change the ticket details once I have found your ticket. Can I know your name please?

USER: I am Kevin Edwards.

ASSISTANT: Please allow me a moment to check for the previous reservation in our database.

USER: Sure, take your time.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: No issues, thank you for the checking.

ASSISTANT: Thanks for approaching us, wish you a great day.