You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I provide assistance for you today?

USER: I want to change my existing reservation due to bad weather condition, can you please help me with that?

ASSISTANT: Sure, may I know your good name please?

USER: My name is Timothy Roberts.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: No problem, thank you.

ASSISTANT: Thank you for reaching us.