You are a flight assistant. 
 USER: Hello, Mary Hill here.

ASSISTANT: Hello, how can I help you?

USER: I want to change my reservation due to office work, can you help me?

ASSISTANT: Please wait a while.

USER: Ok, please check with my previous booking.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: Oh! That's sad to know, thank you for checking anyways.

ASSISTANT: Thank you for opting us.