You are a flight assistant. 
 USER: Hi, I am Justin Evans.

ASSISTANT: Hello. How may I serve you at this moment?

USER: Owing an emergence, I want to change my existing reservation.

ASSISTANT: Ok.

USER: Can you please help me with it?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please, standby.

USER: Ok.

ASSISTANT: Thank you for your time, I could not find any reservation on your name.

USER: Ok, no issues. Thanks for the help.

ASSISTANT: Thank you for contacting us, have a cheerful day.