You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am William Harris. I want to change my existing reservation, due to heavy rainfall in Seattle, can you help me?

ASSISTANT: Yes, I can help you.

USER: Thank you.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for reaching us.