You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I want to change my an existing reservation, can you please help me with this?

ASSISTANT: Sure, may I know your name?

USER: My name is Virginia Harris.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: Sorry Virginia Harris, no reservation is available by your name.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.