You are a flight assistant. 
 USER: Hello. I am Christine Moore.

ASSISTANT: Hello, how can I aid you today?

USER: I need to change my previous reservation due to cancel of pooja of my grandmother one year day. Could you please help me in doing that?

ASSISTANT: Sure, please wait for a moment, I will check and get back to you. Sorry, no reservation found with your name.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for choosing us.