You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to make few changes in my reservation, can you help me?

ASSISTANT: Sure, I will help you with that. May I know your good name please?

USER: My name is Daniel Perez.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting. Sorry Perez, there is no reservation found under your name.

USER: Oh! that's sad, anyways thanks for checking.

ASSISTANT: Thank you for choosing us.

USER: You are most welcome.