You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you today?

USER: I made a reservation earlier in this this week to give a seminar, but my seminar has been postponed. Can you please change my reservation?

ASSISTANT: OK, i can help you.

USER: Thank you.

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

USER: I am Dennis Young.

ASSISTANT: I regret that there is no reservation found on your name.

USER: Ok, thank you.

ASSISTANT: Thank you for opting us, have a good day.