You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change my existing reservation, can you please help me in that?

ASSISTANT: Sure, please let me know your name?

USER: My name is Daniel Phillips.

ASSISTANT: Please wait for a moment. Sorry, no reservation found on your name.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.