You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Myself Stephanie Clark. I would like to spend some more time with my family, so I want to change my existing reservation. Can you please help me?

ASSISTANT: I am happy to help you Clark, I will check your details and get back to you.

USER: Ok.

ASSISTANT: Sorry Clark, I have not found any reservation by your name in our database.

USER: It's ok. Thank you for checking.

ASSISTANT: Thank you for contacting us and have a nice day.