You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I would like to do some modifications in my existing reservation, can you help me in that?

ASSISTANT: Sure, I am here to help you out. Please provide me your name to check the reservation status.

USER: Sure, myself William Lopez.

ASSISTANT: Please allow me a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry William Lopez, there is no reservation on your name in our database.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.