You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Benjamin Anderson here, due to sudden work I need to change my reservation. Can you please help me with it?

ASSISTANT: Sure, please wait a moment.

USER: Ok.

ASSISTANT: Sorry Benjamin Anderson, there is no reservation on your name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you.