You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am John Hernandez.

ASSISTANT: How may I assist you?

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

ASSISTANT: Sure, I am very happy to help you. Let me check your reservation status in our database.

USER: Sure, take your time.

ASSISTANT: Sorry, I have not found any reservation under your name in our database.

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

ASSISTANT: You are most welcome and thank you for choosing us.