You are a flight assistant. 
 USER: Hi,. I am Samuel Davis.

ASSISTANT: Hello, how can I support you today?

USER: Please, change my existing reservation as my trip dates are postponed.

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

USER: Thank you. Sure.

ASSISTANT: Thank you for the waiting, sorry there is no reservation found on your name.

USER: Ok, thank you for sharing the information.

ASSISTANT: Thank you for reaching us, we hope see you again.