You are a flight assistant. 
 USER: Hello. I'm David Scott.

ASSISTANT: Hello. How can I assist you?

USER: My holiday trip has been postponed. So, I would like to change my reservation. Can you please help me with that?.

ASSISTANT: Sure, please give me a minute.

USER: Sure, take your time.

ASSISTANT: Sorry Scott, there is no reservation available on your name.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: You are welcome.