You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you today?

USER: I want to change my reservation as I have some important work at my office. Can you please help me in changing my reservation?

ASSISTANT: Ok, can I know your name to check your previous reservation?

USER: Sure, my name is Eric Mitchell.

ASSISTANT: Please be on hold to check your reservation.

USER: Sure.

ASSISTANT: We regret that, there is no reservation with your name in our records.

USER: Not an issue, anyway thank you for checking.

ASSISTANT: Thank you for reaching us, have a great day.