You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Please help me out in changing my recent reservation.

ASSISTANT: Sure, I am here to help you. May I know your name please?

USER: Dennis Hernandez is my name.

ASSISTANT: Ok, please wait a minute I will get back to you.

USER: Ok.

ASSISTANT: Thank you for your time, sorry we didn't find any reservation on your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us, have a nice day.