You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you for the day?

USER: I am Thomas Carter. My music concert has been postponed, please change my reservation.

ASSISTANT: Sure, please wait I will check your reservation in the database and get back to you.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation found on your name in the database.

USER: That's fine. Anyway, thank you for your help.

ASSISTANT: Thank you for availing us.