You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Stephanie Green.

ASSISTANT: How can I assist you?

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

ASSISTANT: Sure, I'll help you in that. Please be on hold.

USER: Sure, I will wait for your response.

ASSISTANT: Green, there is no reservation found under your name to do changes in that.

USER: Ok, not an issue. May be something went wrong while making the reservation previously. Thank you for providing information.

ASSISTANT: Thank you for choosing us.