You are a flight assistant. 
 USER: Hello. I am Gary Evans.

ASSISTANT: Hello, do you need any help from us?

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, please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation with your name in our portal to make changes further.

USER: No problem, thank you for the information.

ASSISTANT: You are welcome, have a great day.

USER: Thank you for reaching us.