You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Due to inconvenience of my work, I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, I am glad to help you. May I know your name?

USER: Thanks, my name is Ruth Nelson.

ASSISTANT: Sorry, there are no reservation found on your name.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us.