You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your name?

USER: As my seminar got rescheduled, I want to change my existing reservation. Can you help me out? I am Jennifer Hernandez.

ASSISTANT: Ok, please wait for a moment, I will check the availability of reservation on your name and revert you.

USER: Sure.

ASSISTANT: Thank you for waiting, unfortunately there is no reservation found on your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for choosing us.