You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to do some changes in  my existing reservation, can you please help me out?

ASSISTANT: Sure, I will help you in booking. May I know your name to proceed further?

USER: Sure, myself Alexander Hernandez.

ASSISTANT: Alexander Hernandez, regret to inform that there is no active reservation found under your name to amend.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.