You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you for this moment?

USER: I am Sharon Roberts.

ASSISTANT: Glad to meet you, Roberts.

USER: I want to change my existing reservation, due to heavy rainfall in Seattle, can you help me in changing?

ASSISTANT: Sure, I will help you with this. May I know your name please for further process? Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry Roberts, there is no reservation found as per your name to change your reservation.

USER: That's ok, thank you for your information.

ASSISTANT: You are welcome.