You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Can you please assist me in changing my existing reservation?

ASSISTANT: Sure, please share your name?

USER: Kevin Martin.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no active reservation on your given name.

USER: Ok, no problem.

ASSISTANT: Thank you for opting us.

USER: Thank you.