You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I want to change my reservation due to some personal work at home, so please assist me to change.

ASSISTANT: Sure, we are glad to assist you.

USER: Thank you.

ASSISTANT: Please wait for a minute, I will get back to you with current status of your reservation.

USER: Sure, please check my reservation on the name of Joshua Thomas.

ASSISTANT: Ok. Thanks for your patience, no reservation was found on the name of Joshua Thomas in the database.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for choosing us.