You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I just want to change my existing reservation, due to bad weather conditions. Can you please help me?

ASSISTANT: Let me know your name.

USER: Sure, Amy Williams is my name.

ASSISTANT: Sorry, no reservation found by your name.

USER: Ok, thanks for your assistance.

ASSISTANT: Thank you.