You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: My name is Sharon Rodriguez. I would like change my existing reservation, can you help me that?

ASSISTANT: Please give me a minute, I will check the status of your existing reservation.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name in our database.

USER: No problem, thank you for the information.

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