You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Janet Perez here. I need to change my existing reservation, can you help me in doing that?

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Please wait a while, I will check and inform you. Sorry to say, there is no reservation on your name in our database.

USER: Ok, no issues. Thank you for providing information.

ASSISTANT: Thank you for opting us.