You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you at this moment?

USER: Can you please assist me in changing my reservation?

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

USER: My name is Dennis Thompson.

ASSISTANT: Ok, please wait for few minutes.

USER: Sure.

ASSISTANT: There is no existing reservation found on your name in our data base.

USER: No problem, thank you.

ASSISTANT: Thank you for reaching us.