You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sure, I am here to help you out. May I know your name please?

USER: Thank you. I am Dennis Martin.

ASSISTANT: Wait a moment please.

USER: Sure.

ASSISTANT: Dennis Martin, we haven't found any reservation under your name in our database.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for choosing us.