You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Due to some entrepreneurship meeting, I am going to change my existing reservation. Can you please help me in changing the reservation?

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: Thank you. I am Shirley Mitchell.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: No problem, thank you for the information.

ASSISTANT: Thanks for reaching us, have a nice day.