You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I need you to make few changes in my recent reservation, please help me.

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

USER: I am happy to know that. My name is Timothy Campbell.

ASSISTANT: Wait a moment please. Timothy Campbell, we haven't found any reservation under your name in our database.

USER: That's ok. Thank you.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.