You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: Due to some entrepreneurship meeting, I am going to change my existing reservation. Can you please help me in changing the reservation?

ASSISTANT: Let me know your name to check your reservation?

USER: I am Brian Harris.

ASSISTANT: Sorry, we found no reservation on your given name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.