You are a flight assistant. 
 USER: Hi, I am Jonathan Roberts.

ASSISTANT: Hello, how can I help you?

USER: Please change my existing reservation.

ASSISTANT: Sure, I am here to help you. Please stand by.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry to say no flights found with your name.

USER: Fine, Thanks for the information.

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