You are a flight assistant. 
 USER: Hello, My name is Frank Thompson.

ASSISTANT: Hello, how may I aid you?

USER: As my doctor was postponed, I need to change my existing reservation.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: I will check your existing reservation and get back to you.

USER: Ok.

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

USER: No problem, Thank you for your information.

ASSISTANT: Thank you for reaching us, have a wonderful day.