You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: I am Jacob Green.

ASSISTANT: Yes, Jacob.

USER: I want to change my existing reservation due to the sudden change of weather. Please help me with that.

ASSISTANT: Sure. Let me check with your details.

USER: Ok.

ASSISTANT: Sorry to inform you Jacob, there is no reservation found under your name.

USER: That's fine. Thank you for your time.

ASSISTANT: Thank you for reaching us.