You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I am Jacob Mitchell. I want to change my existing reservation, can you please help me with this?

ASSISTANT: Sure, I am here to help you with that. Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry, I could not find any reservation with your name.

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

ASSISTANT: My pleasure.