You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Due to heavy rainfall, I would like to change my existing reservation. Please help me out.

ASSISTANT: Sure, I will help you with the change of flight reservation. May I know your name please?

USER: My name is Helen Gonzalez.

ASSISTANT: Thanks for waiting. But I am sorry to say that there is no reservation on your name.

USER: Ok, no issue. Thank you for your information.