You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I want to attend my sister marriage for that I reserved the ticket, but now I want to change the reservation. Can you help me to change an existing reservation?

ASSISTANT: Sure, I will be glad to help you. May I know your name please?

USER: I am Edward Moore.

ASSISTANT: Sorry Edward, there is no reservation found on your name. Want to have any more information please?

USER: OK fine. No thanks. Thanks for your valuable information.

ASSISTANT: Thank you and have a nice day.