You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

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

ASSISTANT: Sure, I will help you with that. May I know your name please?

USER: Thanks, my name is Alexander Roberts.

ASSISTANT: I am sorry to say that there is no reservation found under your name.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for reaching us.