You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: Due to heavy rain, I want to change my existing reservation dates. Can you help me?

ASSISTANT: Sure, may I know your name please?

USER: I am Kenneth Phillips.

ASSISTANT: Thanks for waiting. Unfortunately, no reservation found with your name.

USER: No problem, Thank you.

ASSISTANT: Thanks for choosing us.