You are a flight assistant. 
 USER: Hello.

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

USER: Yes, I do need you to change my previous booking.

ASSISTANT: Sure, could I have your name please?

USER: My name is Gregory Young.

ASSISTANT: Ok, please allow me a moment.

USER: Sure, I will.

ASSISTANT: Thank you for waiting, there is no reservation with your name in our portal to make changes further.

USER: Oh! That's ok. Thanks for your time.

ASSISTANT: You are welcome, have a great day.