You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am Ryan Lewis. I want to change my existing reservation due to postpone of my science fair. Could you please help me?

ASSISTANT: Sure, I can help you. Give me a minute.

USER: Sure.

ASSISTANT: Thanks for your time. We didn't found any reservation by this name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.