You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Can you please help me in changing my recent reservation?

ASSISTANT: Sure, I will help you.

USER: Ok, thank you for accepting my request.

ASSISTANT: May I know your name please?

USER: Myself Alexander Moore.

ASSISTANT: Sorry Alexander Moore, no reservation found in our database.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for choosing us.