You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Frank Roberts here. I need to change my existing reservation as my plan to go for an historical tour got postponed. Can you please check if my reservation is active or not? if it is active, please change it.

ASSISTANT: Sure, I will help you. Please wait for a moment.

USER: Thank you. Ok, sure.

ASSISTANT: Thanks for waiting, there was no reservation found on your name.

USER: Ok, not a problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for the information.