You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: I am Jack Scott. I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Sorry to inform, no reservation found with your name.

USER: That's ok, no problem. Thank you.

ASSISTANT: Thanks for reaching us.