You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I need to change my recent reservation, due to my trip with my friends has been postponed. Can you please help me to change it?

ASSISTANT: Sure, I am glad to help you. May I know your name please?

USER: Sure, Samuel Johnson is my name.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thank you for waiting, no reservation was found on your name to change.

USER: Ok, thank you.

ASSISTANT: Thank you for availing us.