You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Nicholas Collins.

ASSISTANT: How can I assist you Collins?

USER: As my meeting got postponed at Dallas, can you please help me in changing my existing reservation?

ASSISTANT: I understand your request and will be happy to help you. Please wait for a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry Collins, no reservation found under your name in our database.

USER: Ok, not an issue. Thank you for providing information.