You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you for today?

USER: I am Justin Smith. I would like to change  my reservation as I am having exams, so can you please assist me?

ASSISTANT: Sure, I will help you about it.

USER: Thank you.

ASSISTANT: There is no reservation under your name in our database.

USER: Ok no problem, thank you for your valuable services.

ASSISTANT: Most welcome.