You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hi. How can I help you today?

USER: I want change my reservation, can you help me?

ASSISTANT: Sure, please share your good name.

USER: Myself Gregory Martinez.

ASSISTANT: Please wait for a  moment.

USER: Ok.

ASSISTANT: Sorry Martinez, I did not find any reservation on your name.

USER: No problem, thanks for checking.

ASSISTANT: Most welcome, have a nice day.