You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Lisa Thompson. I want to change my existing reservation due to postpone of my seminar. Could you please help me?

ASSISTANT: Wait a moment please I will revert you back with the proper information.

USER: Sure.

ASSISTANT: Thanks for your time, there is no reservation found on your name to change it.

USER: No problem, thank you for the information.

ASSISTANT: Thanks for reaching us, have a good day.