You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how could I help you now?

USER: My name is Virginia Gonzalez.

ASSISTANT: OK.

USER: I want to change my existing reservation due to postpone of my conference.

ASSISTANT: Ok, please wait. I will go through your reservation.

USER: Sure.

ASSISTANT: Sorry, no reservation has found with your name. Thank you for reaching us.

USER: Not an issue, thank you for your service.