You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: Please help me to change my recent reservation.

ASSISTANT: Sure, I am here to help you out.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Ashley Thomas.

ASSISTANT: Ashley Thomas, we haven't found any reservation under your name in our database.

USER: Thank you for your information.

ASSISTANT: Thank you for choosing us.