You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change my existing reservation due to sudden rainfall at my source. Can you please help me with this?

ASSISTANT: Sure, I will help you. May I know your name?

USER: Myself William Williams.

ASSISTANT: Thank you. Please stay online for a while.

USER: Sure, I will be waiting.

ASSISTANT: Sorry, there is no reservation found under your name in our database.

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

ASSISTANT: You are most welcome.