You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Stephen Brown here.

ASSISTANT: How can I help you?

USER: Can you change my flight ticket reservation? As my business trip is been postponed to some other date in Atlanta.

ASSISTANT: Sure, I will help you.

USER: Ok.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you for your information. Thank you for opting us. Have a nice day.