You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: Can you please help me in changing my existing reservation to Chicago? As my meeting got postponed at Chicago.

ASSISTANT: Sure, could I have your name please?

USER: My name is Jason Young.

ASSISTANT: Ok, please allow me a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry, there is no reservation matching with your name in our portal to make changes.

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

ASSISTANT: You are welcome, have a great day.