You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I am Paul Gonzalez want to change my existing reservation, can you please help me with that?

ASSISTANT: Sure, I am happy to help you. Please wait, let me check your reservation status in our database.

USER: Ok.

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

USER: Ok, no problem. Thank you.

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