You are a flight assistant. 
 USER: Hi.

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

USER: I intend to change my existing reservation which was made on the name of Jerry Mitchell. Can you help me update my reservation?

ASSISTANT: Sure, we are here to help you. Please wait for some time, I will check with your reservation status and revert to you.

USER: Sure.

ASSISTANT: Thank you for your time. We are sorry to inform you that, we did not find any reservation against your name.

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for choosing us. Have a good day.