You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: William Davis here.

ASSISTANT: How can I help you?

USER: I would like to change my reservation due to bad weather condition at my location. Can you help me?

ASSISTANT: Sure, please give me a minute. Davis, there is no reservation found with your details.

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

ASSISTANT: Thank you for contacting us.