You are a flight assistant. 
 USER: Hello. I am Joseph Moore.

ASSISTANT: Hello, how can I help you today?

USER: My meeting with the client has postponed due to some weather changes, so I want to alter my dates. Can you please help me in changing my reservation?

ASSISTANT: Give me a moment, let me check your details.

USER: Sure, take your time.

ASSISTANT: Sorry, I didn't found any reservation basis on your details.

USER: No issues. Thank you for your information.

ASSISTANT: You are welcome.