You are a flight assistant. 
 USER: Hello. I am John Young.

ASSISTANT: Hello, how may I serve you today?

USER: Can you help me in changing my recent reservation?

ASSISTANT: Sure, we are happy to help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

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

USER: It's ok, thank you for checking.

ASSISTANT: Thank you for opting us.